Use rules_jvm_external

[jadenPete]

This issue is part of a broader proposal to merge some of the features in lucidsoftware/rules_scala into this ruleset.

The tracking issue for this effort

The relevant proposal section.

From the proposal:

bazelbuild/rules_scala uses the following rules/macros for fetching external dependencies from Maven (see scala/scala_maven_import_external.bzl).

• java_import_external
• jvm_import_external
• jvm_maven_import_external
• scala_import_external
• scala_maven_import_external

The java_* and jvm_* rules/macros are copied from bazelbuild/bazel (see jvm.bzl and java.bzl), and the scala_* macros use them under the hood.

Today, rules_jvm_external is the standard for fetching external Java and Scala dependencies built with build systems other than Bazel (e.g. Maven), and, in lucidsoftware/rules_scala it’s worked quite well for us. The main advantages are:

• Using external dependencies is as simple as importing rules_jvm_external
• Downloaded artifacts, their checksums, and their versions are “pinned” into a file checked into the repository
• External dependencies can be declared in a single maven_install target instead of each having to be declared in a separate target
• It supports Bzlmod, which should ease a future migration