Update pinot query validator to handle raw time string

[neil-xie]

What changed?
User can pass in raw date string when call ListWorkflowExecutions, ES can handle it when translate SQL into DSL, Pinot need to handle differently since it is using SQL query.

Why?
Handle uncovered case

How did you test it?
Unit test

Potential risks

Release notes

Documentation Changes

[bowenxia]

LGTM

[coveralls]

Pull Request Test Coverage Report for Build 018d9f5c-2972-4f95-b346-1062fb8cc742

Details

• 0 of 21 (100.0%) changed or added relevant lines in 1 file are covered.
• 63 unchanged lines in 12 files lost coverage.
• Overall coverage increased (+0.01%) to 62.73%

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Files with Coverage Reduction	New Missed Lines	%
common/persistence/executionManager.go	2	78.59%
common/persistence/historyManager.go	2	66.67%
common/persistence/sql/sqlplugin/mysql/db.go	2	83.33%
common/persistence/sql/sqlplugin/mysql/task.go	2	73.68%
common/persistence/statsComputer.go	2	94.64%
service/history/task/transfer_active_task_executor.go	2	72.24%
service/history/task/transfer_standby_task_executor.go	2	86.63%
service/history/task/fetcher.go	3	86.6%
service/matching/taskListManager.go	7	79.7%
service/history/shard/context.go	9	66.7%

Totals
Change from base Build 018d9f53-d4dd-496a-b9ac-58b7c581eb4d:	0.01%
Covered Lines:	92500
Relevant Lines:	147458

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💛 - Coveralls