Remove 'tools' from repository

[laeubi]

See

• Migrate the e4 tools to PDE eclipse-pde/eclipse.pde#1081

[github-actions]

Test Results

   918 files  +  298     918 suites  +298   1h 17m 46s ⏱️ + 43m 49s
 7 439 tests  -    28   7 287 ✅  -    23  152 💤  -   5  0 ❌ ±0 
23 466 runs  +7 766  22 958 ✅ +7 609  508 💤 +157  0 ❌ ±0 

Results for commit 55a08b9. ± Comparison against base commit ef61715.

This pull request removes 28 tests.

org.eclipse.e4.tools.compatibility.migration.tests.E4MigrationToolTest ‑ testConvert
org.eclipse.e4.tools.compatibility.migration.tests.E4MigrationToolTest ‑ testFromSource
org.eclipse.e4.tools.persistence.tests.PerspectivePersisterTest ‑ testRestore
org.eclipse.e4.tools.persistence.tests.PerspectivePersisterTest ‑ testSave
org.eclipse.e4.tools.test.FragmentExtractHelperTest ‑ testExtractCommandWithCategory
org.eclipse.e4.tools.test.FragmentExtractHelperTest ‑ testExtractHandlerWithCommand
org.eclipse.e4.tools.test.FragmentExtractHelperTest ‑ testExtractHandlerWithoutCommand
org.eclipse.e4.tools.test.FragmentExtractHelperTest ‑ testExtractPlaceHolder
org.eclipse.e4.tools.test.FragmentExtractHelperTest ‑ testExtractResolveCommandsWithTwoHandledItemsWithSameCommand
org.eclipse.e4.tools.test.FragmentExtractHelperTest ‑ testExtractResolveCommandsWithTwoHandlerWithSameCommand
…