feat: init PgElection #21722

Job	Run time
Build GreptimeDB binary (profile-CI) (ubuntu-20.04)	3m 38s
Build GreptimeDB binaries (ubuntu-20.04)	3m 32s
Check (windows-2022)	3m 29s
Check typos and docs	7s
Check (ubuntu-20.04)	2m 35s
Clippy	3m 45s
Rustfmt	53s
Check License Header	2m 12s
Toml Check	2m 18s
coverage	3m 45s
Sqlness Test (${{ matrix.mode.name }})	1s
Fuzz Test	1s
Fuzz Test (Distributed, ${{ matrix.mode.name }}, ${{ matrix.target }})	1s
Unstable Fuzz Test	1s
Fuzz Test with Chaos (Distributed, ${{ matrix.mode.name }}, ${{ matrix.target }})	1s
	26m 19s

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