[docs] install extras for MacBooks with M1 chip

[felixdittrich92]

This PR:

• add some information to install doctr on MacBooks with M1 chip

Any feedback is welcome 🤗

[codecov]

Codecov Report

Merging #1076 (94484df) into main (6b9f375) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main    #1076   +/-   ##
=======================================
  Coverage   95.23%   95.23%           
=======================================
  Files         142      142           
  Lines        6018     6018           
=======================================
  Hits         5731     5731           
  Misses        287      287           

Flag	Coverage Δ
unittests	95.23% <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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[odulcy-mindee]

Thanks !