Document need to install JDK 8 on Silicon Macs (#3059)

Resolves #3058.

Co-authored-by: Sam Brannen <[email protected]>

Author: marcphilipp

README.md

@@ -65,6 +65,10 @@ task outputs from previous CI builds.
 You need [JDK 17] to build JUnit 5. [Gradle toolchains] are used to detect and
 potentially download additional JDKs for compilation and test execution.
 
+Note: If you're working on a machine with an Apple Silicon processor, you'll need to
+download and install a JDK 8 distribution manually (or via [SDKMAN!] or [asdf]) --
+for example, one from [Zulu] or [Liberica].
+
 All modules can be _built_ with the [Gradle Wrapper] using the following command.
 
 `gradlew clean assemble`
@@ -92,6 +96,7 @@ See also <https://repo1.maven.org/maven2/org/junit/> for releases and
 <https://oss.sonatype.org/content/repositories/snapshots/org/junit/> for snapshots.
 
 
+[asdf]: https://asdf-vm.com/
 [Codecov]: https://codecov.io/gh/junit-team/junit5
 [CONTRIBUTING.md]: https://github.com/junit-team/junit5/blob/HEAD/CONTRIBUTING.md
 [Dependency Metadata]: https://junit.org/junit5/docs/current/user-guide/#dependency-metadata
@@ -101,7 +106,10 @@ See also <https://repo1.maven.org/maven2/org/junit/> for releases and
 [JaCoCo]: https://www.eclemma.org/jacoco/
 [Javadoc]: https://junit.org/junit5/docs/current/api/
 [JDK 17]: https://adoptium.net/archive.html?variant=openjdk17&jvmVariant=hotspot
+[Liberica]: https://bell-sw.com/pages/downloads/
 [Release Notes]: https://junit.org/junit5/docs/current/release-notes/
 [Samples]: https://github.com/junit-team/junit5-samples
+[SDKMAN!]: https://sdkman.io/jdks
 [StackOverflow]: https://stackoverflow.com/questions/tagged/junit5
 [User Guide]: https://junit.org/junit5/docs/current/user-guide/
+[Zulu]: https://www.azul.com/downloads/?version=java-8-lts&os=macos&architecture=arm-64-bit&package=jdk#download-openjdk