Support list for opensearch_version in PluginStats

[Xtansia]

Description

Support list for opensearch_version in PluginStats. Fixes failing tests against unreleased OpenSearch 2.x & main.

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[dblock]

Is there a breaking change being introduced in 2.13? That shouldn't be the case.

[Xtansia]

Is there a breaking change being introduced in 2.13? That shouldn't be the case.

@dblock It's a result of this backport: opensearch-project/OpenSearch#12271

[dblock]

It's a bug, I opened opensearch-project/OpenSearch#12528. Can we avoid this breakage in a different way (mark it pending?).

[Xtansia]

It's a bug, I opened opensearch-project/OpenSearch#12528. Can we avoid this breakage in a different way (mark it pending?).

What exactly do you mean by "mark it pending"? Change the PR to Draft? As presumably we'll still need these changes as the breakage will remain in 3.x?

[dblock]

What exactly do you mean by "mark it pending"? Change the PR to Draft? As presumably we'll still need these changes as the breakage will remain in 3.x?

I mean our build is broken here without this change and we need a workaround, not support for an array. I believe that was a side-effect/mistake and we will not be making a breaking change in 3.0, but I could be wrong.