[HOTFIX] [SQL] Disables Metastore Parquet table conversion for "SQLQuerySuite.CTAS with serde"

Ideally we should convert Metastore Parquet tables with our own Parquet implementation on both read path and write path. However, the write path is not well covered, and causes this test failure. This PR is a hotfix to bring back Jenkins PR builder. A proper fix will be delivered in a follow-up PR.

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Author: Cheng Lian <lian@databricks.com>

Closes #4413 from liancheng/hotfix-parquet-ctas and squashes the following commits:

5291289 [Cheng Lian] Hot fix for "SQLQuerySuite.CTAS with serde"