Adding a sample call to TaskValidator in update workflow cycle

[agautam478]

What changed?
Made some dummy calls and updated the TaskValidation function to. make it compatible with the execution context.
The code is ready to be handed over to the future devs of this feature.

Added a dynamic config variable in order to control these calls on the basis of the domain ID.

Why?
The changes are made to test the TaskValidatiion functionality, see it's feasibility in the update flow and to prepare a dummy call instance so that it can be enabled right away.

How did you test it?
Yes. The feature comes with a unit test.

Potential risks
NA

Release notes
NA

Documentation Changes
NA

[coveralls]

Pull Request Test Coverage Report for Build 018d65eb-5d8b-43a6-a191-9c3bc14cb586

• -11 of 22 (50.0%) changed or added relevant lines in 2 files are covered.
• 48 unchanged lines in 11 files lost coverage.
• Overall coverage increased (+0.02%) to 62.721%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
service/history/execution/context.go	0	11	0.0%

Files with Coverage Reduction	New Missed Lines	%
common/task/weighted_round_robin_task_scheduler.go	1	89.05%
service/history/execution/context.go	1	69.81%
common/persistence/sql/common.go	2	72.73%
common/persistence/sql/sqlplugin/mysql/db.go	2	83.33%
common/persistence/sql/sqlplugin/mysql/task.go	2	73.68%
common/util.go	2	91.69%
service/history/task/fetcher.go	2	85.57%
service/matching/taskListManager.go	2	79.7%
service/history/task/cross_cluster_task_processor.go	8	80.79%
common/taskvalidator/validateworkflow.go	11	67.5%

Totals
Change from base Build 018d6588-230d-4a34-870a-29b5fd08321e:	0.02%
Covered Lines:	92244
Relevant Lines:	147070

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💛 - Coveralls