chore: Applied post release modifications v0.5.1

[felixdittrich92]

This PR introduces the following modifications:

• updated pypi badge in README
• updated documentation
• updated package version index

Any feedback is welcome!

[codecov]

Codecov Report

Merging #870 (8691fb7) into main (9d03085) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #870   +/-   ##
=======================================
  Coverage   94.82%   94.82%           
=======================================
  Files         133      133           
  Lines        5200     5200           
=======================================
  Hits         4931     4931           
  Misses        269      269           

Flag	Coverage Δ
unittests	94.82% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
doctr/transforms/modules/base.py	94.59% <0.00%> (ø)

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[charlesmindee]

That's perfect, thank you!

[frgfm]

Missing labels here as well :)

[felixdittrich92]

@frgfm do you have a short snippet what was missing :)

[frgfm]

I mean PR labels that @charlesmindee can apply here 👍

[felixdittrich92]

ah ok so i was thinking i have missed anything 😅