Push aggregate in LookupIndex

[Nivras]

What type of PR is this?

• bug
• feature
• enhancement

What does this PR do?

LookupIndexRequest can receive the statProps info, and do aggregate in storage.

This PR add a new node(IndexAggregateNode) for LookupIndexPlan, it will check and append the columns which in statProp but not in returnColumns, and append it in returnColumns.

IndexProjectNode before this PR will return the row in the order of returnColumns, after this PR, it will return returnColumns + statProps(which the statProp not in returnColumns). and IndexAggregateNode will truncate the Row, only real returnColumns append into resultDataSet, and calculate the aggregate expression and return the result.

Which issue(s)/PR(s) this PR relates to?

Special notes for your reviewer, ex. impact of this fix, etc:

Additional context/ Design document:

Checklist:

• Documentation affected (Please add the label if documentation needs to be modified.)
• Incompatibility (If it breaks the compatibility, please describe it and add the corresponding label.）
• If it's needed to cherry-pick (If cherry-pick to some branches is required, please label the destination version(s).)
• Performance impacted: Consumes more CPU/Memory

Release notes:

Please confirm whether to be reflected in release notes and how to describe:

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[critical27]

Goood job~~ Generally LGTM, clean code

[critical27]

Good job~

[cangfengzhs]

LGTM