fix(ci): bump markdownlint

[lukashroch]

Update markdownlint:

• fixes dead links
• re-lint *.MD files

[codecov-commenter]

Codecov Report

Merging #1470 (76b942f) into master (75a0be8) will not change coverage.
The diff coverage is n/a.

❗ Current head 76b942f differs from pull request most recent head 476c6ff. Consider uploading reports for the commit 476c6ff to get more accurate results

@@           Coverage Diff           @@
##           master    #1470   +/-   ##
=======================================
  Coverage   95.10%   95.10%           
=======================================
  Files         117      117           
  Lines        1123     1123           
  Branches      128      128           
=======================================
  Hits         1068     1068           
  Misses         23       23           
  Partials       32       32           

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[WikiRik]

I think we should keep the old table of contents list instead of adding all smaller headers as well. Apart from that it looks good

[WikiRik]

Forgot these three