[lldb][Progress] Fix test for trimmed progress reports (#78357)

The test TestTrimmedProgressReporting tests that progress reports are
being sent by listening for events with the titles of specific progress
reports. Commit f1ef910b removed the report for Apple DWARF indices
which was one of the reports being listened for in this test, so that
report is removed here as well.

That commit also now creates all progress reports with details so
reports string are prepended with the details count. This changes the
length of the trimmed progress report title string that's checked for
here so this commit changes the string to match as well.

This test was skipped on non-Apple platforms, but since the progress
report for Apple DWARF indices has been removed this commit removes that
decorator.