feat: Add TeX support

[ianlewis]

Description:

Add support for TeX files. The SUPPORTED_LANGUAGES.md file is now sorted.

Related Issues:

Updates #460

Checklist:

• Review the CONTRIBUTING.md documentation.
• Add a reference to a related issue in the repository.
• Add a description of the changes proposed in the pull request.
• Add unit tests if applicable.
• Add a note in the CHANGELOG.md if applicable.
• Sign the Google CLA.

[codecov]

Codecov Report

Merging #766 (1fa78a5) into main (3f14b78) will increase coverage by 0.48%.
The diff coverage is n/a.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #766      +/-   ##
==========================================
+ Coverage   80.50%   80.99%   +0.48%     
==========================================
  Files          19       18       -1     
  Lines        1144     1126      -18     
  Branches       14       14              
==========================================
- Hits          921      912       -9     
+ Misses        160      154       -6     
+ Partials       63       60       -3     

see 1 file with indirect coverage changes