`JdtTextTestSuite` `PluginsNotLoadedTest.pluginsNotLoaded` fails intermittently

The test `PluginsNotLoadedTest.pluginsNotLoaded` fails intermittently with the stack trace:
```
java.lang.AssertionError:
Wrong bundles loaded:
- org.eclipse.jdt.junit
expected:<0> but was:<24>
at org.junit.Assert.fail(Assert.java:89)
at org.junit.Assert.failNotEquals(Assert.java:835)
at org.junit.Assert.assertEquals(Assert.java:647)
at org.eclipse.jdt.text.tests.PluginsNotLoadedTest.pluginsNotLoaded(PluginsNotLoadedTest.java:278)
```

Something must have changed in the platform to cause this test to fail.

PRs might be blamed for this issue while they have nothing to do with it.

See:
https://github.com/eclipse-jdt/eclipse.jdt.ui/pull/1747
https://github.com/eclipse-jdt/eclipse.jdt.ui/pull/1741
https://github.com/eclipse-jdt/eclipse.jdt.ui/pull/1707 (looks like MD file change)

All have the same test failure

Last of all I've created a dumb PR changing the date in the license header - the same test has failed: https://github.com/eclipse-jdt/eclipse.jdt.ui/pull/1753

Start with PluginsNotLoadedTest.pluginsNotLoaded at PluginsNotLoadedTest.java:278 and run the JdtTextTestSuite repeatedly to observe the intermittent failure. Compare the failures with pull requests 1747, 1741, 1707, and 1753. Done means identifying the platform change or test condition causing org.eclipse.jdt.junit to load unexpectedly and confirming the test is reliable.

Written by the indexing model from the issue text.