feat: Possible to skip cosign toolchains registration #1624

Job	Run time
matrix-prep-bazelversion	5s
matrix-prep-os	1s
test (ubuntu-latest, 7.1.1, ., true)	7m 10s
test (ubuntu-latest, 7.1.1, ., false)	4m 29s
test (ubuntu-latest, 7.1.1, e2e/wasm, false)	4m 11s
test (ubuntu-latest, 7.1.1, e2e/smoke, true)	16s
test (ubuntu-latest, 7.1.1, e2e/smoke, false)	2m 27s
test (ubuntu-latest, 7.1.1, e2e/assertion, true)	4m 57s
test (ubuntu-latest, 6.4.0, ., true)	7m 51s
test (ubuntu-latest, 6.4.0, ., false)	4m 42s
test (ubuntu-latest, 6.4.0, e2e/wasm, false)	2m 49s
test (ubuntu-latest, 6.4.0, e2e/smoke, true)	17s
test (ubuntu-latest, 6.4.0, e2e/smoke, false)	2m 26s
test (ubuntu-latest, 6.4.0, e2e/assertion, true)	5m 23s
	47m 4s

Provide feedback