Support JAVABIN (from java_binary) as an env variable for specifying the JVM for bazel run

[plaird]

We support the env variable BAZEL_RUN_JAVA to allow the user to override the JVM to be used for bazel run invocations. The Bazel java_binary() rule has the JAVABIN convention for the same purpose.

• BAZEL_RUN_JAVA: https://github.com/salesforce/rules_spring/blob/main/springboot/bazelrun.md#launcher-jvm
• JAVABIN: https://bazel.build/reference/be/java#java_binary

We should make JAVABIN as a secondary env variable that will be consulted to look for the JVM. This will take precendene over the Bazel toolchain JVM configs, and JAVA_HOME.

[plaird]

This is technically an enhancement, but this feature is only used during bazel run invocations, which is typically only done on developer machines. And probably few users already have JAVABIN defined.

So this can go in a patch release, I think that is ok.