Add more guards around batched migration execution

What does this MR do and why?

This MR is yet another step towards Execute batched background migrations in parallel (#372316 - closed).

It adds two additional checks in order to meet couple of the requirements listed in #372316 (closed):

• Do not execute migrations that target the same table at the same .
• Do not execute jobs from the same migration at the same time.

It also add a feature flag check that was missed in Extract batched migration execution as dedicate... (!102585 - merged).

As we currently execute only one migration at a time, there is no change in behavior because of these new checks.

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #372316 (closed)