feat: returning warning instead of error on unsupported `SET` stateme… #20013

Job	Run time
Check typos and docs	10s
Build GreptimeDB binary (profile-CI) (ubuntu-20.04)	3m 13s
Build GreptimeDB binaries (ubuntu-20.04)	2m 44s
Check (windows-2022)	8m 58s
Check (ubuntu-20.04)	2m 18s
Clippy	3m 48s
coverage	15m 11s
Rustfmt	1m 1s
Check License Header	2m 13s
Toml Check	31s
Sqlness Test (Basic)	2m 43s
Fuzz Test (fuzz_create_table)	4m 54s
Sqlness Test (Remote WAL)	3m 11s
Fuzz Test (fuzz_alter_table)	6m 40s
Fuzz Test (fuzz_create_database)	4m 42s
Fuzz Test (fuzz_create_logical_table)	4m 43s
Fuzz Test (fuzz_alter_logical_table)	4m 36s
Fuzz Test (fuzz_insert)	4m 42s
Fuzz Test (fuzz_insert_logical_table)	5m 9s
Unstable Fuzz Test (unstable_fuzz_create_table_standalone)	6m 38s
Fuzz Test with Chaos (Distributed, Remote WAL, fuzz_migrate_mito_regions)	7m 6s
Fuzz Test (Distributed, Remote WAL, fuzz_create_table)	7m 9s
Fuzz Test with Chaos (Distributed, Remote WAL, fuzz_failover_mito_regions)	7m 11s
Fuzz Test (Distributed, Remote WAL, fuzz_alter_table)	7m 4s
Fuzz Test with Chaos (Distributed, Remote WAL, fuzz_failover_metric_regions)	7m 36s
Fuzz Test (Distributed, Remote WAL, fuzz_create_database)	7m 51s
Fuzz Test (Distributed, Remote WAL, fuzz_create_logical_table)	7m 25s
Fuzz Test (Distributed, Remote WAL, fuzz_alter_logical_table)	7m 0s
Fuzz Test (Distributed, Remote WAL, fuzz_insert)	6m 52s
Fuzz Test (Distributed, Remote WAL, fuzz_insert_logical_table)	7m 0s
	2h 40m 19s

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