Enforce new line coverage 85%

[taylanisikdemir]

What changed?
Trying codecov's patch coverage setting to enforce new line coverage per diff to be > 85%.

How did you test it?
I added a new dummy function without tests in the first commit on this PR. Codecov patch check failed with below message:

Then I added tests to cover half of the lines:

Then I removed the dummy function so PR only has yml changes:

[codecov]

Codecov Report

Merging #5805 (b73923e) into master (cff5a94) will increase coverage by 0.01%.
The diff coverage is n/a.

Additional details and impacted files

see 6 files with indirect coverage changes

---

Continue to review full report in Codecov by Sentry.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update cff5a94...b73923e. Read the comment docs.

[coveralls]

Pull Request Test Coverage Report for Build 018e6249-5b94-4d76-8d8d-11d84d4b9f8d

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 22 unchanged lines in 7 files lost coverage.
• Overall coverage increased (+0.02%) to 65.383%

---

Files with Coverage Reduction	New Missed Lines	%
common/task/weighted_round_robin_task_scheduler.go	2	89.05%
common/task/fifo_task_scheduler.go	2	84.54%
common/util.go	2	91.78%
common/persistence/statsComputer.go	3	94.64%
service/history/task/fetcher.go	3	85.57%
service/matching/taskListManager.go	4	79.7%
service/history/task/transfer_standby_task_executor.go	6	86.6%

Totals
Change from base Build 018e61ef-a6f4-4969-adc1-af73494586b3:	0.02%
Covered Lines:	95576
Relevant Lines:	146178

---

💛 - Coveralls

[davidporter-id-au]

discussed offline that we don't expect this to hit a problem with the nondeterministic coverage problem due to it being patch related only