Release rules_jvm_external 6.3

[comius]

The new release should include:
#1226

The PR makes it possible to use a single rules_java version on Bazel 6.x and 7.

[comius]

@shs96c are there any blockers to proceed with the release? I'm asking, becuase I'm blocked on moving java_proto_libraries into protobuf repository by this.

[shs96c]

I want to land #1232 before we release 6.3

[shs96c]

That's in. I'll wait a little longer for #1208 to be updated, since that's a useful fix, but I plan on releasing 6.3 next week

[comius]

I was hoping for something sooner, because this release is on a critical path to Bazel 8 release. Basically I need rules_jvm_release, so that I can put java_proto_library into protobuf repo. Then I need protobuf release so that I can remove *_proto_libraries from Bazel before it's cut.

[shs96c]

We can always do another release with #1208 in. Let me check with the other maintainers, but I think we can get this out today or tomorrow if we need to.

[vinnybod]

@shs96c I will be out for ~1 week and won't be updating #1208 til then