CompatHelper: bump compat for SpecialFunctions in [extras] to 2, (keep existing compat)

[github-actions]

This pull request changes the compat entry for the SpecialFunctions package from 0.8, 0.9, 0.10, 1 to 0.8, 0.9, 0.10, 1, 2.
This keeps the compat entries for earlier versions.

Note: I have not tested your package with this new compat entry.
It is your responsibility to make sure that your package tests pass before you merge this pull request.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 6.23%. Comparing base (fee2294) to head (87da73c).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@          Coverage Diff           @@
##           master    #150   +/-   ##
======================================
  Coverage    6.23%   6.23%           
======================================
  Files         189     189           
  Lines        9853    9853           
======================================
  Hits          614     614           
  Misses       9239    9239           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.