Bump sphinx from 3.3.1 to 3.4.0 (#552)

Bumps [sphinx](https://github.com/sphinx-doc/sphinx) from 3.3.1 to 3.4.0.
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a href="https://github.com/sphinx-doc/sphinx/blob/3.x/CHANGES">sphinx's changelog</a>.</em></p>
<blockquote>
<h1>Release 3.4.0 (released Dec 20, 2020)</h1>
<h2>Incompatible changes</h2>
<ul>
<li><a href="https://github-redirect.dependabot.com/sphinx-doc/sphinx/issues/8105">#8105</a>: autodoc: the signature of class constructor will be shown for decorated
classes, not a signature of decorator</li>
</ul>
<h2>Deprecated</h2>
<ul>
<li>The <code>follow_wrapped</code> argument of <code>sphinx.util.inspect.signature()</code></li>
<li>The <code>no_docstring</code> argument of
<code>sphinx.ext.autodoc.Documenter.add_content()</code></li>
<li><code>sphinx.ext.autodoc.Documenter.get_object_members()</code></li>
<li><code>sphinx.ext.autodoc.DataDeclarationDocumenter</code></li>
<li><code>sphinx.ext.autodoc.GenericAliasDocumenter</code></li>
<li><code>sphinx.ext.autodoc.InstanceAttributeDocumenter</code></li>
<li><code>sphinx.ext.autodoc.SlotsAttributeDocumenter</code></li>
<li><code>sphinx.ext.autodoc.TypeVarDocumenter</code></li>
<li><code>sphinx.ext.autodoc.importer._getannotations()</code></li>
<li><code>sphinx.ext.autodoc.importer._getmro()</code></li>
<li><code>sphinx.pycode.ModuleAnalyzer.parse()</code></li>
<li><code>sphinx.util.osutil.movefile()</code></li>
<li><code>sphinx.util.requests.is_ssl_error()</code></li>
</ul>
<h2>Features added</h2>
<ul>
<li><a href="https://github-redirect.dependabot.com/sphinx-doc/sphinx/issues/8119">#8119</a>: autodoc: Allow to determine whether a member not included in
<code>__all__</code> attribute of the module should be documented or not via
:event:<code>autodoc-skip-member</code> event</li>
<li><a href="https://github-redirect.dependabot.com/sphinx-doc/sphinx/issues/8219">#8219</a>: autodoc: Parameters for generic class are not shown when super class is
a generic class and show-inheritance option is given (in Python 3.7 or above)</li>
<li>autodoc: Add <code>Documenter.config</code> as a shortcut to access the config object</li>
<li>autodoc: Add Optional[t] to annotation of function and method if a default
value equal to None is set.</li>
<li><a href="https://github-redirect.dependabot.com/sphinx-doc/sphinx/issues/8209">#8209</a>: autodoc: Add <code>:no-value:</code> option to :rst:dir:<code>autoattribute</code> and
:rst:dir:<code>autodata</code> directive to suppress the default value of the variable</li>
<li><a href="https://github-redirect.dependabot.com/sphinx-doc/sphinx/issues/8460">#8460</a>: autodoc: Support custom types defined by typing.NewType</li>
<li><a href="https://github-redirect.dependabot.com/sphinx-doc/sphinx/issues/8285">#8285</a>: napoleon: Add :confval:<code>napoleon_attr_annotations</code> to merge type hints
on source code automatically if any type is specified in docstring</li>
<li><a href="https://github-redirect.dependabot.com/sphinx-doc/sphinx/issues/8236">#8236</a>: napoleon: Support numpydoc's &quot;Receives&quot; section</li>
<li><a href="https://github-redirect.dependabot.com/sphinx-doc/sphinx/issues/6914">#6914</a>: Add a new event :event:<code>warn-missing-reference</code> to custom warning
messages when failed to resolve a cross-reference</li>
<li><a href="https://github-redirect.dependabot.com/sphinx-doc/sphinx/issues/6914">#6914</a>: Emit a detailed warning when failed to resolve a <code>:ref:</code> reference</li>
<li><a href="https://github-redirect.dependabot.com/sphinx-doc/sphinx/issues/6629">#6629</a>: linkcheck: The builder now handles rate limits. See
:confval:<code>linkcheck_retry_on_rate_limit</code> for details.</li>
</ul>
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</blockquote>
<p>... (truncated)</p>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a href="https://github.com/sphinx-doc/sphinx/commit/79ff24815442211286754b2457fbb13c1b7810e4"><code>79ff248</code></a> Bump to 3.4.0 final</li>
<li><a href="https://github.com/sphinx-doc/sphinx/commit/61fd867b37290b776ae1aa2c24f0687cefc82eb4"><code>61fd867</code></a> Merged CHANGES for 3.3.2 into 3.4.0 (unreleased)</li>
<li><a href="https://github.com/sphinx-doc/sphinx/commit/723294f9227cb20841230904bb18ae566df04e29"><code>723294f</code></a> Merge pull request <a href="https://github-redirect.dependabot.com/sphinx-doc/sphinx/issues/8556">#8556</a> from tk0miya/8549_gettext_compact=0</li>
<li><a href="https://github.com/sphinx-doc/sphinx/commit/1977f3fceeab1f9132a5096993f243f1a76fd0f5"><code>1977f3f</code></a> Fix <a href="https://github-redirect.dependabot.com/sphinx-doc/sphinx/issues/8549">#8549</a>: i18n: <code>-D gettext_compact=0</code> is no longer working</li>
<li><a href="https://github.com/sphinx-doc/sphinx/commit/6e8ea8572fc10bd6b04211bb69d096409dab9ec4"><code>6e8ea85</code></a> Merge pull request <a href="https://github-redirect.dependabot.com/sphinx-doc/sphinx/issues/8552">#8552</a> from tk0miya/8236_napoleon_receives_section</li>
<li><a href="https://github.com/sphinx-doc/sphinx/commit/7f1284f2e780ce720483f50da863690641fc1c51"><code>7f1284f</code></a> Merge pull request <a href="https://github-redirect.dependabot.com/sphinx-doc/sphinx/issues/8555">#8555</a> from tk0miya/8512_test_comment</li>
<li><a href="https://github.com/sphinx-doc/sphinx/commit/2fa15e93963512e540eed3a9fa92575079e2642b"><code>2fa15e9</code></a> Merge pull request <a href="https://github-redirect.dependabot.com/sphinx-doc/sphinx/issues/8551">#8551</a> from tk0miya/8365_pydomain_xref_missing_context</li>
<li><a href="https://github.com/sphinx-doc/sphinx/commit/9a9d7f3f00e852c266d3da9762b6e72d9bf9679a"><code>9a9d7f3</code></a> test: Add comment for UnicodeEncodeError handler (refs: <a href="https://github-redirect.dependabot.com/sphinx-doc/sphinx/issues/8512">#8512</a>)</li>
<li><a href="https://github.com/sphinx-doc/sphinx/commit/aae2f199114381e899f5c273749c95944062afd0"><code>aae2f19</code></a> Merge pull request <a href="https://github-redirect.dependabot.com/sphinx-doc/sphinx/issues/8512">#8512</a> from jbms/fix-nonascii_srcdir</li>
<li><a href="https://github.com/sphinx-doc/sphinx/commit/f50b999911232548ca99798f22c653c624e615ec"><code>f50b999</code></a> Close <a href="https://github-redirect.dependabot.com/sphinx-doc/sphinx/issues/8236">#8236</a>: napoleon: Support numpydoc's &quot;Receives&quot; section</li>
<li>Additional commits viewable in <a href="https://github.com/sphinx-doc/sphinx/compare/v3.3.1...v3.4.0">compare view</a></li>
</ul>
</details>
<br />


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requirements/doc.txt

@@ -1 +1 @@
-sphinx==3.3.1
+sphinx==3.4.0