feat: protect datanode with concurrency limit. #20007

Job	Run time
Build GreptimeDB binaries (ubuntu-20.04)	3m 7s
Check (windows-2022)	10m 41s
Build GreptimeDB binary (profile-CI) (ubuntu-20.04)	3m 0s
Check (ubuntu-20.04)	2m 5s
Check typos and docs	7s
Clippy	3m 44s
coverage	14m 31s
Rustfmt	53s
Check License Header	2m 8s
Toml Check	23s
Unstable Fuzz Test (unstable_fuzz_create_table_standalone)	6m 35s
Fuzz Test with Chaos (Distributed, Remote WAL, fuzz_migrate_mito_regions)	9m 36s
Fuzz Test (Distributed, Remote WAL, fuzz_create_table)	8m 56s
Fuzz Test with Chaos (Distributed, Remote WAL, fuzz_failover_mito_regions)	7m 23s
Fuzz Test (Distributed, Remote WAL, fuzz_alter_table)	9m 39s
Fuzz Test with Chaos (Distributed, Remote WAL, fuzz_failover_metric_regions)	9m 4s
Fuzz Test (Distributed, Remote WAL, fuzz_create_database)	9m 27s
Fuzz Test (Distributed, Remote WAL, fuzz_create_logical_table)	8m 35s
Fuzz Test (Distributed, Remote WAL, fuzz_alter_logical_table)	7m 30s
Fuzz Test (Distributed, Remote WAL, fuzz_insert)	8m 50s
Fuzz Test (Distributed, Remote WAL, fuzz_insert_logical_table)	6m 58s
Fuzz Test (fuzz_create_table)	6m 27s
Fuzz Test (fuzz_alter_table)	6m 36s
Sqlness Test (Basic)	2m 41s
Fuzz Test (fuzz_create_database)	6m 34s
Sqlness Test (Remote WAL)	3m 13s
Fuzz Test (fuzz_create_logical_table)	6m 32s
Fuzz Test (fuzz_alter_logical_table)	4m 58s
Fuzz Test (fuzz_insert)	6m 48s
Fuzz Test (fuzz_insert_logical_table)	6m 23s
	3h 3m 24s

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