Add generic OAuth support

[mantas-sidlauskas]

What changed?
Adding generic JWT token validation. JWKS setting is needed to retrieve correct public key from issuer.
Group information and Admin flag is extracted from token using JMESPath query.

Why?
This change allows server to validate not only self-signed JWT tokens, but users can use any Identity provider they want. Cadence SDK client has to add acquired JWT token to RPC call.

How did you test it?
Unit tests

Potential risks

Release notes

Documentation Changes

[coveralls]

Pull Request Test Coverage Report for Build 018d9e90-20c5-4e9a-acb6-0a774abbf364

Details

• -23 of 89 (74.16%) changed or added relevant lines in 2 files are covered.
• 68 unchanged lines in 11 files lost coverage.
• Overall coverage decreased (-0.01%) to 62.681%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
common/config/authorization.go	9	14	64.29%
common/authorization/oauthAuthorizer.go	57	75	76.0%

Files with Coverage Reduction	New Missed Lines	%
common/task/fifo_task_scheduler.go	2	85.57%
service/history/execution/mutable_state_builder.go	2	68.64%
service/history/execution/mutable_state_util.go	2	37.63%
service/history/task/fetcher.go	2	85.57%
service/matching/taskReader.go	2	83.55%
common/persistence/nosql/nosqlplugin/cassandra/workflow.go	3	59.55%
service/matching/taskListManager.go	3	80.2%
service/history/task/transfer_standby_task_executor.go	6	86.21%
service/history/task/cross_cluster_task_processor.go	8	80.79%
common/persistence/nosql/nosqlplugin/cassandra/workflow_parsing_utils.go	14	83.26%

Totals
Change from base Build 018d9e76-e756-47fd-9c9c-a574b6b76d81:	-0.01%
Covered Lines:	92338
Relevant Lines:	147315

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💛 - Coveralls