Allow org.eclipse.jdt.junit.core access to internal methods

To distinguish between JUnit 5 and JUnit 6 annotations when launching tests, we potentially look into manifests.

In order to use PackageFragmentRoot.getManifest() to this end,
org.eclipse.jdt.junit.core is now in the friends list of package org.eclipse.jdt.internal.core.

Fixes #4663

Author: trancexpress

org.eclipse.jdt.core/META-INF/MANIFEST.MF

@@ -23,7 +23,7 @@ Export-Package: org.eclipse.jdt.core,
  org.eclipse.jdt.internal.codeassist.select;x-friends:="org.eclipse.jdt.core.tests.model, org.eclipse.jdt.core.tests.compiler, org.eclipse.jdt.core.tests.builder, org.eclipse.jdt.core.tests.performance, org.eclipse.jdt.ui.tests",
  org.eclipse.jdt.internal.compiler;x-friends:="org.eclipse.jdt.apt.pluggable.core, org.eclipse.jdt.core.tests.model, org.eclipse.jdt.core.tests.compiler, org.eclipse.jdt.core.tests.builder, org.eclipse.jdt.core.tests.performance, org.eclipse.jdt.ui.tests",
  org.eclipse.jdt.internal.compiler.parser;x-friends:="org.eclipse.jdt.apt.pluggable.core, org.eclipse.jdt.core.tests.model, org.eclipse.jdt.core.tests.compiler, org.eclipse.jdt.core.tests.builder, org.eclipse.jdt.core.tests.performance, org.eclipse.jdt.ui.tests",
- org.eclipse.jdt.internal.core;x-friends:="org.eclipse.jdt.apt.pluggable.core,org.eclipse.pde.api.tools,org.eclipse.jdt.launching, org.eclipse.jdt.core.tests.model, org.eclipse.jdt.core.tests.compiler, org.eclipse.jdt.core.tests.builder, org.eclipse.jdt.core.tests.performance, org.eclipse.jdt.ui.tests",
+ org.eclipse.jdt.internal.core;x-friends:="org.eclipse.jdt.apt.pluggable.core,org.eclipse.pde.api.tools,org.eclipse.jdt.launching,org.eclipse.jdt.junit.core,org.eclipse.jdt.core.tests.model, org.eclipse.jdt.core.tests.compiler, org.eclipse.jdt.core.tests.builder, org.eclipse.jdt.core.tests.performance, org.eclipse.jdt.ui.tests",
  org.eclipse.jdt.internal.core.builder;x-friends:="org.eclipse.jdt.apt.pluggable.core,org.eclipse.pde.api.tools, org.eclipse.jdt.core.tests.model, org.eclipse.jdt.core.tests.compiler, org.eclipse.jdt.core.tests.builder, org.eclipse.jdt.core.tests.performance, org.eclipse.jdt.ui.tests",
  org.eclipse.jdt.internal.core.dom;x-friends:="org.eclipse.jdt.core.tests.model, org.eclipse.jdt.core.tests.compiler, org.eclipse.jdt.core.tests.builder, org.eclipse.jdt.core.tests.performance, org.eclipse.jdt.ui.tests",
  org.eclipse.jdt.internal.core.dom.rewrite;x-friends:="org.eclipse.jdt.core.tests.model, org.eclipse.jdt.core.tests.compiler, org.eclipse.jdt.core.tests.builder, org.eclipse.jdt.core.tests.performance, org.eclipse.jdt.ui.tests",