[Bazel] Stop using rules_jvm_external default maven repository name

[joca-bt]

The protobuf Bazel module depends on rules_jvm_external and it's including the artifacts it needs under the default maven repository name (@maven, https://github.com/protocolbuffers/protobuf/blob/main/WORKSPACE#L65). This can create some issues for rules_jvm_external users, as described in bazel-contrib/rules_jvm_external#1168.

Is it necessary for these artifacts to be under the default maven repository name? Otherwise, could we use a different name for the maven repository so it won't conflict with other modules or users' projects (https://github.com/bazelbuild/rules_jvm_external?tab=readme-ov-file#multiple-maven_installjson-files)? This should also lead to a better isolation of this module.

For example:

maven_install(
    name = "maven_protobuf",
    ...
)

[joca-bt]

Addressed in #19477