…and removed the no-shuffle tag.

This PR fixes #142376 by fixing the flaky test in language_version_test.dart and removes the no-shuffle tag.
 
## The Problem
The test expected the language version that is set at the top of the test file ('2.13' set in language_version_test.dart – line 14) but defaulted to the language version set in the file it is testing ('2.12' is set in language_version.dart).

This problem was hidden when some other test ran before this test and set up the language version correctly.
 
## The Fix
Make the test itself load the default language version we are testing against.