cherry-pick #448 to release-4.0

What problem does this PR solve?

In SQL restore. we choose one session to execute SQL,
so we can't simple use dbPool to create table concurrently.

What is changed and how it works?

In restore. if we are using SQL glue.OwnerStorage() will return false.
so we use this condition to tell whether we should make dbPool or not.

Check List

Tests

• Manual test (add detailed scripts or steps below)
  test will include in brie: update test to create mutli tables tidb#18993

Code changes

• Has exported function/method change
• Has exported variable/fields change
• Has interface methods change
• Has persistent data change

Side effects

• Possible performance regression
• Increased code complexity
• Breaking backward compatibility

Related changes

• Need to cherry-pick to the release branch
• Need to update the documentation

Release Note

• No release note