Docker: add datasource and dashboards to Grafana

[mantas-sidlauskas]

What changed?
Prometheus data source and Grafana dashboards are ready to use from the beginning, no manual actions are needed. Additionally, default auth form in Grafana is disabled.

Why?
To get dashboards working without any manual steps

How did you test it?
Local test

Potential risks

Release notes

Documentation Changes

[coveralls]

Pull Request Test Coverage Report for Build 018811e6-627d-4d93-84fa-5df284bc0eda

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 100 unchanged lines in 15 files lost coverage.
• Overall coverage decreased (-0.06%) to 57.21%

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Files with Coverage Reduction	New Missed Lines	%
common/persistence/historyManager.go	2	66.67%
common/task/weightedRoundRobinTaskScheduler.go	2	88.6%
service/history/execution/mutable_state_task_refresher.go	2	59.81%
service/history/execution/mutable_state_util.go	2	35.95%
service/history/task/transfer_active_task_executor.go	2	72.16%
common/cache/lru.go	3	91.71%
common/persistence/statsComputer.go	3	93.57%
service/history/task/fetcher.go	3	91.75%
common/persistence/serialization/parser.go	4	63.91%
common/persistence/serialization/thrift_decoder.go	4	57.14%

Totals
Change from base Build 0188117b-6107-4218-aae1-536d976d0ed0:	-0.06%
Covered Lines:	86866
Relevant Lines:	151837

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💛 - Coveralls

[davidporter-id-au]

nice!