docs(index): add changelog

Adds link to changelog to documentation index. Currently, there is no
option to format the python semantic release Changelog as rst, and the
myst_parser for Sphinx (appears to) require the whole documentation to
be in Markdown. As such, a simple rst include directive doesn't work
here. Until one of the 2 above issues gets sorted, we default to linking
to the Github release history, which contains the whole changelog.

docs/index.rst

@@ -47,8 +47,11 @@ If you want to learn more about the analysis,
 you should look at :ref:`analysis`.
 The source code documentation lives at :ref:`source`.
 If testing is your thing, peek at :ref:`testing`.
+A full changelog can be found with the `release history`_.
 And you can learn about contributing at :ref:`contributing`.
 
+.. _release history: https://github.com/IMS-Bio2Core-Facility/BIC086/releases
+
 Welcome!
 
 .. toctree::