Bump pyyaml from 5.3.1 to 5.4

Bumps [pyyaml](https://github.com/yaml/pyyaml) from 5.3.1 to 5.4.
- [Release notes](https://github.com/yaml/pyyaml/releases)
- [Changelog](https://github.com/yaml/pyyaml/blob/master/CHANGES)
- [Commits](yaml/pyyaml@5.3.1...5.4)

Signed-off-by: dependabot[bot] <[email protected]>

requirements.txt

@@ -4,39 +4,95 @@
 #
 #    pip-compile
 #
-appdirs==1.4.3            # via black
-attrs==19.3.0             # via black, flake8-mypy
-bandit==1.6.2             # via flake8-bandit
+appdirs==1.4.3
+    # via black
+attrs==19.3.0
+    # via
+    #   black
+    #   flake8-mypy
+bandit==1.6.2
+    # via flake8-bandit
 black==19.10b0
-click==7.1.1              # via black
-entrypoints==0.3          # via flake8
+    # via
+    #   -r requirements.in
+    #   flake8-black
+click==7.1.1
+    # via black
+entrypoints==0.3
+    # via flake8
 flake8-bandit==2.1.2
+    # via -r requirements.in
 flake8-black==0.1.1
+    # via -r requirements.in
 flake8-blind-except==0.1.1
+    # via -r requirements.in
 flake8-codeclimate==0.3.0
+    # via -r requirements.in
 flake8-debugger==3.2.1
+    # via -r requirements.in
 flake8-imports==0.1.1
+    # via -r requirements.in
 flake8-mypy==17.8.0
-flake8-polyfill==1.0.2    # via flake8-bandit
+    # via -r requirements.in
+flake8-polyfill==1.0.2
+    # via flake8-bandit
 flake8==3.7.9
-gitdb==4.0.2              # via gitpython
-gitpython==3.1.0          # via bandit
+    # via
+    #   -r requirements.in
+    #   flake8-bandit
+    #   flake8-black
+    #   flake8-codeclimate
+    #   flake8-debugger
+    #   flake8-imports
+    #   flake8-mypy
+    #   flake8-polyfill
+gitdb==4.0.2
+    # via gitpython
+gitpython==3.1.0
+    # via bandit
 isort==4.3.21
+    # via
+    #   -r requirements.in
+    #   flake8-imports
 mccabe==0.6.1
-mypy-extensions==0.4.3    # via mypy
-mypy==0.770               # via flake8-mypy
-pathspec==0.7.0           # via black
-pbr==5.4.4                # via stevedore
-pycodestyle==2.5.0        # via flake8, flake8-bandit, flake8-debugger
-pyflakes==2.1.1           # via flake8
-pyyaml==5.3.1             # via bandit
-regex==2020.2.20          # via black
-six==1.14.0               # via bandit, stevedore
-smmap==3.0.1              # via gitdb
-stevedore==1.32.0         # via bandit
-toml==0.10.0              # via black
-typed-ast==1.4.1          # via black, mypy
-typing-extensions==3.7.4.1  # via mypy
+    # via
+    #   -r requirements.in
+    #   flake8
+mypy-extensions==0.4.3
+    # via mypy
+mypy==0.770
+    # via flake8-mypy
+pathspec==0.7.0
+    # via black
+pbr==5.4.4
+    # via stevedore
+pycodestyle==2.5.0
+    # via
+    #   flake8
+    #   flake8-bandit
+    #   flake8-debugger
+pyflakes==2.1.1
+    # via flake8
+pyyaml==5.4
+    # via bandit
+regex==2020.2.20
+    # via black
+six==1.14.0
+    # via
+    #   bandit
+    #   stevedore
+smmap==3.0.1
+    # via gitdb
+stevedore==1.32.0
+    # via bandit
+toml==0.10.0
+    # via black
+typed-ast==1.4.1
+    # via
+    #   black
+    #   mypy
+typing-extensions==3.7.4.1
+    # via mypy
 
 # The following packages are considered to be unsafe in a requirements file:
 # setuptools