feat(spanner/spansql): support fine-grained access control DDL syntax

[nktks]

This PR supports fine-grained access control DDL syntax parsing.

• CREATE ROLE
• DROP ROLE
• GRANT
• REVOKE

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[rahul2393]

Thanks @nktks for this, please fix the conflicts.

[nktks]

@rahul2393 Thank you! I fixed conflict and following function name change.

[toga4]

Are there any obstacles other than conflicts in proceeding with this PR?
We are waiting for this PR to be merged.

[nktks]

@toga4 Thanks for your reminding.

I fixed conflicts and modified code not to change exist func name (like parseCommaList, parseTableOrIndexOrColumnName, parseColumnNameList) for avoiding compile error when other PR's changes include these function.

@rahul2393 Could you please take a look this PR?

Thank you!