Added unit tests for history handler

[timl3136]

What changed?
Added more unit tests for history handler

Why?
Improve test coverage and stability

How did you test it?
Unit tests

Potential risks

Release notes

Documentation Changes

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 65.01%. Comparing base (b4bbae4) to head (3636c7b).
Report is 1 commits behind head on master.

Additional details and impacted files

see 8 files with indirect coverage changes

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[coveralls]

Pull Request Test Coverage Report for Build 018f595f-7d5a-46db-9c87-49c5efddbd0d

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 48 unchanged lines in 12 files lost coverage.
• Overall coverage increased (+0.008%) to 68.51%

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Files with Coverage Reduction	New Missed Lines	%
common/task/weighted_round_robin_task_scheduler.go	2	89.05%
common/cache/lru.go	2	92.89%
service/matching/taskListManager.go	2	80.65%
common/membership/hashring.go	2	84.69%
common/persistence/historyManager.go	2	66.67%
service/history/task/transfer_standby_task_executor.go	3	86.21%
service/history/task/task.go	3	84.81%
common/persistence/statsComputer.go	3	96.07%
service/history/task/fetcher.go	4	85.05%
service/history/execution/cache.go	6	74.61%

Totals
Change from base Build 018f5920-e167-45cd-8901-b0a5fa3bbbfc:	0.008%
Covered Lines:	100628
Relevant Lines:	146881

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💛 - Coveralls