Cherrypick "add MasterMetrics periodic logging" to 6.3.

[RenxuanW]

Cherrypicking #4626. Add logging to master role to count the number of requests of each type received. This helps to determine whether the master is making progress. We need it in 6.3 to debug master-stall issues.

20210608-205053-renxuan-8cec4d1d58f255fb compressed=True data_size=21416213 duration=4360671 ended=102460 fail_fast=10 max_runs=100000 pass=100001 priority=100 remaining=0 runtime=0:29:03 sanity=False started=102565 stopped=20210608-211956 submitted=20210608-205053 timeout=5400 username=renxuan

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[foundationdb-ci]

AWS CodeBuild CI Report

• CodeBuild project: foundationdb-pull-request-build
• Commit ID: 6dcf863
• Result: FAILED
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[foundationdb-ci]

AWS CodeBuild CI Report

• CodeBuild project: foundationdb-pull-request-build
• Commit ID: 9d7d3e1
• Result: FAILED
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[halfprice]

Can you make sure the CodeBuild pass?

[RenxuanW]

Can you make sure the CodeBuild pass?

It's an unrelated failure. I just ran the test locally, it passed.

[foundationdb-ci]

AWS CodeBuild CI Report

• CodeBuild project: foundationdb-pull-request-build
• Commit ID: 529a3a4
• Result: FAILED
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[foundationdb-ci]

AWS CodeBuild CI Report

• CodeBuild project: foundationdb-pull-request-build
• Commit ID: 1170cba
• Result: FAILED
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[foundationdb-ci]

AWS CodeBuild CI Report

• CodeBuild project: foundationdb-pull-request-build
• Commit ID: 33355a8
• Result: SUCCEEDED
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[foundationdb-ci]

AWS CodeBuild CI Report

• CodeBuild project: foundationdb-pull-request-build
• Commit ID: f17a49d
• Result: SUCCEEDED
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