support endpointParams in pulsar oauth

[qizichao-dm]

Support endpointParams in pulsar oauth and parameters including audience could be set after this PR.

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Fixes #5069

Relates to kedacore/keda-docs#1243

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[zroubalik]

/run-e2e pulsar
Update: You can check the progress here

[qizichao-dm]

@zroubalik Will this change be cherry-picked to 2.12? From the roadmap, 2.13 is next year and I want to use this feature sooner.

[zroubalik]

@qizichao-dm we usually don't backport features, just security and critical patches