Add GraalVM 21.1.0

[nicokosi]

See https://github.com/graalvm/graalvm-ce-builds/releases/tag/vm-21.1.0

Not sure if we can document the macOS tweak:

If you are using macOS Catalina and later you may need to remove the quarantine attribute from the bits before you can use them
To do this, run the following:

$ sudo xattr -r -d com.apple.quarantine path/to/graalvm/folder/

[nicokosi]

Java 8 Linux aarch64 link is broken 😭 :
https://github.com/graalvm/graalvm-ce-builds/releases/download/vm-21.1.0/graalvm-ce-java8-linux-aarch64-21.1.0.tar.gz

Seems not available from tag: https://github.com/graalvm/graalvm-ce-builds/releases/tag/vm-21.1.0.
I think I can remove the link.

[eddumelendez]

@nicokosi thanks for the PR but we are running java candidates from here.