build(deps): update rcgen requirement from 0.11.3 to 0.12.0 #1270

Job	Run time
Clippy	27s
Format	14s
Cargo Deny	14s
Check for documentation errors (stable)	30s
Check for documentation errors (beta)	28s
MSRV	1m 36s
Check for documentation errors (nightly)	28s
Cargo Package	26s
Check cross compilation targets	38s
Build+test (--all-features, stable)	43s
Build+test (stable, ubuntu-20.04)	32s
Build+test (--features=alloc, stable, ubuntu-20.04)	34s
Validate external types appearing in public API	58s
Build+test (--no-default-features, stable, ubuntu-20.04)	28s
Build+test (--no-default-features --features alloc,std, stable, ubuntu-20.04)	26s
Build+test (--all-features, --release, stable, ubuntu-20.04)	1m 27s
Measure coverage	41s
Build+test (--all-features, nightly, ubuntu-20.04)	45s
Verify that no-std modes do not rely on libstd (--no-default-features)	11s
Build+test (--all-features, beta, ubuntu-20.04)	39s
Verify that no-std modes do not rely on libstd (--no-default-features --features alloc)	15s
Build+test (--no-default-features --features alloc,std,aws_lc_rs, stable, macos-latest)	1m 33s
Build+test (--no-default-features --features alloc,std,aws_lc_rs, stable, windows-latest)	3m 38s
Check semver compatibility	27s
Build+test (--no-default-features --features alloc,std,aws_lc_rs, stable, ubuntu-latest)	46s
Feature Powerset	39s
	19m 43s

Provide feedback