CompatHelper: bump compat for Turing to 0.28 for package ppl, (keep existing compat)

[github-actions]

This pull request changes the compat entry for the Turing package from 0.24, 0.25 to 0.24, 0.25, 0.28 for package ppl.
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

Patch and project coverage have no change.

Comparison is base (1b7c135) 96.89% compared to head (49d37da) 96.90%.

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #373   +/-   ##
=======================================
  Coverage   96.89%   96.90%           
=======================================
  Files          10       11    +1     
  Lines         387      388    +1     
=======================================
+ Hits          375      376    +1     
  Misses         12       12           

see 1 file with indirect coverage changes

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