Remove java.* packages from Import-Package headers in all jars (#4738)

... to maximize compatibility with older OSGi runtimes.

Resolves #4733.

(cherry picked from commit f045ef6)

Author: marcphilipp

documentation/src/docs/asciidoc/release-notes/release-notes-5.13.4.adoc

@@ -10,6 +10,16 @@ link:{junit-framework-repo}+/milestone/101?closed=1+[5.13.4] milestone page in t
 repository on GitHub.
 
 
+[[release-notes-5.13.4-overall-improvements]]
+=== Overall Changes
+
+[[release-notes-5.13.4-overall-new-features-and-improvements]]
+==== New Features and Improvements
+
+* Remove `java.*` packages from `Import-Package` headers in all jar manifests to maximize
+  compatibility with older OSGi runtimes.
+
+
 [[release-notes-5.13.4-junit-platform]]
 === JUnit Platform
 

gradle/plugins/common/src/main/kotlin/junitbuild.osgi-conventions.gradle.kts

@@ -65,6 +65,11 @@ tasks.withType<Jar>().named {
 				# Instruct the APIGuardianAnnotations how to operate.
 				# See https://bnd.bndtools.org/instructions/export-apiguardian.html
 				-export-apiguardian: *;version=${'$'}{versionmask;===;${'$'}{version_cleanup;${'$'}{task.archiveVersion}}}
+
+				# Avoid including java packages in Import-Package header to maximize compatibility with older OSGi runtimes.
+				# See https://bnd.bndtools.org/instructions/noimportjava.html
+				# Issue: https://github.com/junit-team/junit-framework/issues/4733
+				-noimportjava: true
 			"""
 		)