Adding unit tests for TestPrepareTransferTasksForWorkflowTxn

[agautam478]

What changed?
Adding unit tests for TestPrepareTransferTasksForWorkflowTxn

Why?
code coverage increase.

How did you test it?
unit test

Potential risks

Release notes

Documentation Changes

[codecov]

Codecov Report

Merging #5763 (ff01b7b) into master (51f592f) will increase coverage by 0.03%.
The diff coverage is n/a.

❗ Current head ff01b7b differs from pull request most recent head 9567d06. Consider uploading reports for the commit 9567d06 to get more accurate results

Additional details and impacted files

see 6 files with indirect coverage changes

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[coveralls]

Pull Request Test Coverage Report for Build 018e3e25-8a83-4b99-ae9f-d9baa09d8c64

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 104 unchanged lines in 16 files lost coverage.
• Overall coverage decreased (-0.06%) to 64.799%

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Files with Coverage Reduction	New Missed Lines	%
service/history/task/transfer_standby_task_executor.go	2	86.6%
common/persistence/sql/sqlplugin/mysql/task.go	2	73.68%
tools/cli/admin_db_decode_thrift.go	2	70.51%
service/matching/db.go	2	73.23%
service/history/task/transfer_active_task_executor.go	2	72.38%
service/matching/taskListManager.go	2	79.7%
service/matching/matcher.go	2	90.72%
service/history/execution/mutable_state_util.go	2	78.48%
common/membership/hashring.go	2	82.23%
common/persistence/sql/sqlplugin/mysql/db.go	2	79.49%

Totals
Change from base Build 018e3e1f-7237-4565-99da-b08c08f40c4f:	-0.06%
Covered Lines:	94451
Relevant Lines:	145760

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💛 - Coveralls