Add unit tests for execution/context.go ReapplyEvents

[Shaddoll]

What changed?
Add unit tests for execution/context.go ReapplyEvents

Why?
improve coverage

How did you test it?
unit tests

Potential risks

Release notes

Documentation Changes

[codecov]

Codecov Report

Merging #5848 (7333abd) into master (5ecb9f9) will decrease coverage by 0.07%.
The diff coverage is 100.00%.

❗ Current head 7333abd differs from pull request most recent head f1744b1. Consider uploading reports for the commit f1744b1 to get more accurate results

Additional details and impacted files

Files	Coverage Δ
service/history/execution/context.go	38.54% <100.00%> (+6.69%)	⬆️

... and 5 files with indirect coverage changes

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[coveralls]

Pull Request Test Coverage Report for Build 018ea4c1-f553-47c5-9638-f662828e32b6

Details

• 6 of 6 (100.0%) changed or added relevant lines in 1 file are covered.
• 57 unchanged lines in 15 files lost coverage.
• Overall coverage increased (+0.005%) to 65.894%

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Files with Coverage Reduction	New Missed Lines	%
service/history/task/transfer_standby_task_executor.go	2	87.84%
service/matching/taskReader.go	2	83.55%
common/task/weighted_round_robin_task_scheduler.go	2	88.56%
common/task/parallel_task_processor.go	2	93.06%
client/history/client.go	2	78.22%
service/history/handler/handler.go	2	49.66%
common/util.go	2	91.78%
service/matching/taskListManager.go	2	79.7%
common/persistence/errors.go	3	0.0%
service/frontend/api/handler.go	4	62.11%

Totals
Change from base Build 018ea24f-029a-4402-92bd-731131d907a5:	0.005%
Covered Lines:	96429
Relevant Lines:	146339

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💛 - Coveralls