Fix the broken release links to include the v [ci skip]

[eric-wieser]

Our tag names start with v, but the default for releases is to not use a v.

https://galgebra--407.org.readthedocs.build/en/407/changelog.html

This fixes the tags, but breaks the "next release" link...

xref bitprophet/releases#65

[codecov]

Codecov Report

Merging #407 into master will increase coverage by 0.02%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #407      +/-   ##
==========================================
+ Coverage   77.69%   77.71%   +0.02%     
==========================================
  Files          16       16              
  Lines        4205     4205              
==========================================
+ Hits         3267     3268       +1     
+ Misses        938      937       -1     

Impacted Files	Coverage Δ
galgebra/atoms.py	97.67% <0.00%> (+1.16%)	⬆️

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[utensil]

Your workaround should have fixed the Next Release link, but the rendered doc is still broken?

[utensil]

Oh,

pickling environment... failed

Traceback (most recent call last):
  File "/home/docs/checkouts/readthedocs.org/user_builds/galgebra/envs/407/src/sphinx/sphinx/cmd/build.py", line 280, in build_main
    app.build(args.force_all, filenames)
  File "/home/docs/checkouts/readthedocs.org/user_builds/galgebra/envs/407/src/sphinx/sphinx/application.py", line 348, in build
    self.builder.build_update()
  File "/home/docs/checkouts/readthedocs.org/user_builds/galgebra/envs/407/src/sphinx/sphinx/builders/__init__.py", line 299, in build_update
    len(to_build))
  File "/home/docs/checkouts/readthedocs.org/user_builds/galgebra/envs/407/src/sphinx/sphinx/builders/__init__.py", line 328, in build
    pickle.dump(self.env, f, pickle.HIGHEST_PROTOCOL)
_pickle.PicklingError: Can't pickle <class '_releases_release_uri'>: attribute lookup _releases_release_uri on builtins failed

Exception occurred:
  File "/home/docs/checkouts/readthedocs.org/user_builds/galgebra/envs/407/src/sphinx/sphinx/builders/__init__.py", line 328, in build
    pickle.dump(self.env, f, pickle.HIGHEST_PROTOCOL)
_pickle.PicklingError: Can't pickle <class '_releases_release_uri'>: attribute lookup _releases_release_uri on builtins failed
The full traceback has been saved in /tmp/sphinx-err-7m_mqaah.log, if you want to report the issue to the developers.
Please also report this if it was a user error, so that a better error message can be provided next time.
A bug report can be filed in the tracker at <https://github.com/sphinx-doc/sphinx/issues>. Thanks!

[eric-wieser]

Will see if I can come up with a working workaround

[eric-wieser]

Moving it to its own file seems to do the trick

[utensil]

I should have voiced out my doubts.