Bug Report

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According to mysql's doc, max_execution_time only works for select sql, in TiDB, it try to align this behavior, however, there is still some corner cases which max_execution_time affect non select sql, for example, in #56923, it tries to set context's timeout using max_execution_time, so rpc can be aware of max_execution_time, but it actually does not check InSelectStmt, which means a non select sql will be affected by this pr.

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