Add version constraints to junit-platform-launcher added in plug-in l…

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Streamline compile error resolution proposals and strengthen typing

Remove eclipse32.png because it's not in the build.properties anyway

eclipse-platform/eclipse.platform#2261

Copy JUnit 5 tests for JUnit 6 tests

Fixes #2111

PDE should not warn if resource URI of unknown scheme cannot be found

Fixes #2031

Fix intermittent JUnit5 test failure by adding timeout to session res…

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Fix intermittent JUnit5 test failure by adding timeout to session res…

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Fix intermittent JUnit5 test failure by adding timeout to session res…

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Fix intermittent JUnit5 test failure by adding timeout to session res…

…ult poll

Fix intermittent JUnit5 test failure by adding timeout to session res…

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