Make eclipse.core.tools aboutText static to prevent comparator errors

[HannesWell]

This should prevent the current comparator error in I-builds, which are:

1.  eclipse.platform/runtime/bundles/org.eclipse.core.tools/.polyglot.META-INF
   no-classifier: different
      about.mappings: properties files differ
         0: baseline='I20260219-0810' != reactor='I20260219-1800'
    The main artifact has been replaced with the baseline version.
    The following attached artifacts have been replaced with the baseline version: [sources]

@iloveeclipse, @akurtakov WDYT?

[github-actions]

Test Results

 1 977 files  ±0   1 977 suites  ±0   1h 34m 23s ⏱️ - 3m 17s
 4 743 tests ±0   4 719 ✅ ±0   24 💤 ±0  0 ❌ ±0 
14 229 runs  ±0  14 047 ✅ ±0  182 💤 ±0  0 ❌ ±0 

Results for commit 7c9fcd0. ± Comparison against base commit 9035292.