add issue and PR directives for sphinx

[CagtayFabry]

format as seen in the xarray docs but we can adopt to a different style, I like the idea though

result: https://weldx--658.org.readthedocs.build/en/658/changelog_link.html

Changes

• links issues/PRs in sphinx with specific code directive

Checks

• updated CHANGELOG.rst
• updated doc/

[codecov]

Codecov Report

Merging #658 (7d16ffc) into master (79d7257) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #658   +/-   ##
=======================================
  Coverage   96.18%   96.18%           
=======================================
  Files          91       91           
  Lines        5867     5867           
=======================================
  Hits         5643     5643           
  Misses        224      224           

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[github-actions]

Unit Test Results

       1 files  ±0         1 suites  ±0   1m 55s ⏱️ +9s
1 936 tests ±0  1 936 ✔️ ±0  0 💤 ±0  0 ❌ ±0 

Results for commit 7d16ffc. ± Comparison against base commit 79d7257.

♻️ This comment has been updated with latest results.

[CagtayFabry]

let me know what you think of this format @vhirtham @marscher 🚀

[vhirtham]

let me know what you think of this format @vhirtham @marscher 🚀

This is really nice 👌 . Couldn't remember the rst link syntax and c&p'd them every time. This one is rather easy to memorize. 😉

[marscher]

That one will make our lives easier (will now write changelog entries like crazy) :)

Thank you!

[CagtayFabry]

That one will make our lives easier (will now write changelog entries like crazy) :)

Thank you!

sadly rstfmt doesn't work with this because it doesn't know the directive
oh well, it was fun while it lasted 🤷‍♂️

(you can go back to 2 spaces now as well)