bugfix: support hashdata tableam in Orca

[gongxun0928]

closes: #ISSUE_Number

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Change logs

RetrieveRelStorageType add a magic number 7015. we use the am_id(7015) we
assigned to the custom table am, and let the orca optimizer treat this
columnar storage format as AOCS to generate an execution plan

At present, there is no way to extend orca to support custom table am. So here we use the am_id(7015) we assigned to the custom table am, and let the orca optimizer treat this columnar storage format as AOCS to generate an execution plan
Why use the magic number 7015 instead of the macro definition? Just to make it look like it doesn't make sense, so others will notice that the logic needs to be refactored

Why are the changes needed?

we defined a custom table am using columnar storage, but the orca optimizer does not support am other than HEAP/AO/AOCS.

Does this PR introduce any user-facing change?

If yes, please clarify the previous behavior and the change this PR proposes.

How was this patch tested?

Please detail how the changes were tested, including manual tests and any relevant unit or integration tests.

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[my-ship-it]

LGTM