docs(theme): upgrade mkdocs-material to 8.x

[heitorlessa]

Issue #, if available: #990

Description of changes:

This upgrades mkdocs-material to 8.x, addresses breaking changes, and enable two new features: code block annotations and anchor tracking.

Checklist

• Meet tenets criteria
• Update tests
• Update docs
• PR title follows conventional commit semantics
• Enable new version warning

Breaking change checklist

RFC issue #:

• Migration process documented
• Implement warnings (if it can live side by side)

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

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View rendered docs/index.md

[codecov-commenter]

Codecov Report

Merging #1002 (7811df8) into develop (b52b430) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop    #1002   +/-   ##
========================================
  Coverage    99.96%   99.96%           
========================================
  Files          119      119           
  Lines         5347     5347           
  Branches       610      610           
========================================
  Hits          5345     5345           
  Partials         2        2           

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