feat: Modify Column Type #14985

Job	Run time
Toml Check	42s
Build GreptimeDB binaries (ubuntu-20.04)	4m 4s
Clippy	2m 4s
Check (windows-latest)	5m 52s
Rustfmt	22s
Check (ubuntu-20.04)	1m 36s
Spell Check with Typos	20s
coverage	13m 1s
Sqlness Test with Kafka Wal (ubuntu-20.04)	2m 39s
Fuzz Test (fuzz_create_table)	9m 55s
Compatibility Test	28s
Fuzz Test (fuzz_alter_table)	9m 39s
Fuzz Test (fuzz_create_database)	9m 27s
Sqlness Test (ubuntu-20.04)	1m 48s
	1h 1m 57s

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