explain the purpose of the job in the github actions

Author: ferrine

.github/workflows/pypi.yml

@@ -17,6 +17,9 @@ concurrency:
   cancel-in-progress: true
 
 jobs:
+  # The job to build pypi wheels users can installed precompiled for them.
+  # At the moment only linux wheels are build, Windows and MacOS will compile on installation
+  # Before prebuilds all users had to compile code anyway.
   build:
     strategy:
       matrix: