QA: normalize versions to [lts,1] (drop pre) (#520)

The [QA] group (Aqua/JET) should run on LTS + latest stable only, never
on the prerelease channel. Normalize [QA].versions from ["1","lts","pre"]
to the canonical ["lts","1"].

Co-authored-by: ChrisRackauckas-Claude <accounts@chrisrackauckas.com>
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: 3 people

test/test_groups.toml

@@ -2,7 +2,7 @@
 versions = ["1", "lts", "pre"]
 
 [QA]
-versions = ["1", "lts", "pre"]
+versions = ["lts", "1"]
 
 [ModelingToolkitSIExt]
 versions = ["1"]