TT-13421 create indexes on sharded sql pumps

[sredxny]

Description

Related Issue

Motivation and Context

How This Has Been Tested

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• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

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[jeffy-mathew]

do we need waitgroup when create background is false?

[jeffy-mathew]

@sredxny since we're using gorm, shall we explore the possibility of using NamingStrategy in gorm config?