[PROPOSAL] Replace direct plugin download by maven dependencies for bcw
What/Why
What are you proposing?
Coming from https://github.com/opensearch-project/cross-cluster-replication/pull/566#issuecomment-1262653097, replace any direct download of the latest plugin zip such as https://github.com/opensearch-project/job-scheduler/pull/242 by a maven dependency.
Document how to do this in https://github.com/opensearch-project/opensearch-plugins/blob/main/TESTING.md#backwards-compatibility-testing
What users have asked for this feature?
See https://github.com/opensearch-project/cross-cluster-replication/pull/566#issuecomment-1262653097. This would reduce the amount of code needed for bcw.
What problems are you trying to solve?
Standardize dependency management for bcw across plugins.
before this is done in the other repositories, https://github.com/opensearch-project/OpenSearch/issues/4589 should be solved so that the code can be further simplified. the current hack with RegularFile creates a lot of unnecessary overhead and goes directly against what the javadoc of RegularFile says (i.e.: never construct it yourself).