Remove comments containing version number following pinned GH actions calls

Description

Remove all GH action versions from workflow files comments.

Why we are doing it

We moved to pinned hashes from (human readable) versions for all GH actions. We left the original version number in the comment following the GH action reference. Unfortunately, versions in the comment are not updated by dependabot. See the following example:

https://github.com/opensearch-project/opensearch-prometheus-exporter/pull/565 was dependabot's bump of actions/setup-java from 5.4.0 to 5.5.0:

-        uses: actions/setup-java@1bcf9fb12cf4aa7d266a90ae39939e61372fe520 # v5
+        uses: actions/setup-java@0f481fcb613427c0f801b606911222b5b6f3083a # v5

As we can see the version in the comment was already outdated and did not get update again (perhaps dependabot is not capable of doing it anyway).