Fail in JavaSearchBugsTests.testBug181488a

See: https://download.eclipse.org/eclipse/downloads/drops4/I20260320-1800/testresults/html/org.eclipse.jdt.core.tests.model_ep440I-unit-linux-x86_64-java26_linux.gtk.x86_64_26.html

```
Index file should be unchanged!!! expected:<1774055635716> but was:<1774055636937>

junit.framework.AssertionFailedError: Index file should be unchanged!!! expected:<1774055635716> but was:<1774055636937>
at junit.framework.Assert.fail(Assert.java:57)
at junit.framework.Assert.failNotEquals(Assert.java:329)
at junit.framework.Assert.assertEquals(Assert.java:78)
at junit.framework.Assert.assertEquals(Assert.java:159)
at junit.framework.TestCase.assertEquals(TestCase.java:302)
at org.eclipse.jdt.core.tests.model.JavaSearchBugsTests.testBug181488a(JavaSearchBugsTests.java:8786)
```

Relevant part of the workspace log:

[testBug181488a.txt](https://github.com/user-attachments/files/26160013/testBug181488a.txt)