Add tests for ReadHistoryBranch

[jakobht]

What changed?
Add tests for ReadHistoryBranch

Why?

How did you test it?

Potential risks

Release notes

Documentation Changes

[codecov]

Codecov Report

Merging #5899 (a769f0c) into master (1fd00b5) will increase coverage by 0.04%.
The diff coverage is n/a.

Additional details and impacted files

see 7 files with indirect coverage changes

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[coveralls]

Pull Request Test Coverage Report for Build 018ef572-b3be-461b-9daf-b84bb462de14

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 65 unchanged lines in 13 files lost coverage.
• Overall coverage decreased (-0.005%) to 67.589%

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Files with Coverage Reduction	New Missed Lines	%
common/task/weighted_round_robin_task_scheduler.go	2	88.56%
common/persistence/sql/sqlplugin/mysql/task.go	2	73.68%
service/frontend/api/handler.go	2	62.04%
service/matching/db.go	2	73.23%
service/history/queue/transfer_queue_processor.go	2	57.17%
common/persistence/sql/sqlplugin/mysql/db.go	2	79.49%
common/log/tag/tags.go	3	50.46%
common/archiver/filestore/historyArchiver.go	4	80.95%
service/history/task/task_util.go	4	69.43%
common/task/fifo_task_scheduler.go	5	84.54%

Totals
Change from base Build 018ef47c-7ef1-4ce1-b4c9-3fa25bfb5bee:	-0.005%
Covered Lines:	98976
Relevant Lines:	146438

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💛 - Coveralls