Add argument to ci for test threads and build jobs #55959

Job	Run time
build (windows-latest)	3s
build (ubuntu-latest)	7s
check-bevy-internal-imports	6s
build (macos-latest)	15s
check-doc	13s
ci	15s
check-missing-examples-in-docs	20s
miri	8s
run-examples-macos-metal	7s
toml	12s
typos	6s
msrv	1s
build-wasm	1s
build-wasm-atomics	1s
check-compiles	1s
check-compiles-no-std	1s
check-missing-features-in-docs	1s
markdownlint	1m 3s
	3m 1s

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