Use pool for MultiValue container #1118

Job	Run time
Rustfmt	12s
Build (ubuntu-22.04, stable, lua54)	31s
Build (ubuntu-22.04, stable, lua53)	31s
Clippy (lua54)	16s
Build (ubuntu-22.04, stable, lua52)	24s
Clippy (lua53)	12s
Build (ubuntu-22.04, stable, lua51)	13s
Clippy (lua52)	15s
Build (ubuntu-22.04, stable, luajit)	31s
Clippy (lua51)	17s
Build (ubuntu-22.04, stable, luau)	30s
Clippy (luajit)	13s
Build (ubuntu-22.04, stable, luau-jit)	30s
Clippy (luau)	13s
Build (ubuntu-22.04, stable, luau-vector4)	33s
Clippy (luau-jit)	10s
Build (macos-latest, stable, lua54)	1s
Clippy (luau-vector4)	15s
Build (macos-latest, stable, lua53)	20s
Build (macos-latest, stable, lua52)	23s
Build (macos-latest, stable, lua51)	19s
Build (macos-latest, stable, luajit)	33s
Build (macos-latest, stable, luau)	1s
Build (macos-latest, stable, luau-jit)	1s
Build (macos-latest, stable, luau-vector4)	34s
Build (windows-latest, stable, lua54)	1s
Build (windows-latest, stable, lua53)	25s
Build (windows-latest, stable, lua52)	24s
Build (windows-latest, stable, lua51)	24s
Build (windows-latest, stable, luajit)	17s
Build (windows-latest, stable, luau)	27s
Build (windows-latest, stable, luau-jit)	17s
Build (windows-latest, stable, luau-vector4)	16s
Cross-compile to aarch64-apple-darwin	0s
Cross-compile to aarch64-unknown-linux-gnu	0s
Cross-compile to armv7-unknown-linux-gnueabihf	0s
Test	0s
Test modules	0s
Test modules on Windows	0s
Test with address sanitizer	0s
Test on wasm32-unknown-emscripten	0s
	10m 29s

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