In the "spec" file for RPM builds, handle the debug server tests different from the standard server.


support-files/mysql.spec.sh:
  Don't use the "test-bt" target to run the tests on the debug server,
  rather use "test-bt-debug".
  
  There are two reasons for this:
  1) Consistency with the "tar.gz" builds.
  2) The tool that evaluates the build logs needs unique "--comment=" options in the log,
     or else it will fail when it generates the test status summary.