move to 2021 edition #544

Job	Run time
linting	1m 41s
internal-tests (ardupilotmega)	1m 10s
mavlink-dump	50s
internal-tests (asluav)	1m 47s
msrv	4m 27s
internal-tests (matrixpilot)	1m 36s
internal-tests (minimal)	1m 11s
internal-tests (paparazzi)	1m 13s
formatting	5s
internal-tests (python_array_test)	1m 16s
internal-tests (slugs)	1m 13s
internal-tests (standard)	1m 2s
internal-tests (test)	1m 4s
internal-tests (ualberta)	1m 16s
internal-tests (uavionix)	1m 3s
internal-tests (icarous)	59s
internal-tests (common)	1m 1s
docs	31s
build (macos-latest, x86_64-apple-darwin, --features ardupilotmega)	1m 27s
build (ubuntu-latest, arm-unknown-linux-musleabihf, --features ardupilotmega)	2m 4s
build (ubuntu-latest, armv7-unknown-linux-musleabihf, --features ardupilotmega)	1m 59s
build (ubuntu-latest, x86_64-unknown-linux-musl, --features ardupilotmega)	2m 4s
build (ubuntu-latest, x86_64-unknown-linux-musl, --features ardupilotmega,emit-description,emit-e...	2m 7s
build (ubuntu-latest, thumbv7m-none-eabi, --no-default-features --features embedded)	1m 14s
build (windows-latest, x86_64-pc-windows-msvc, --features ardupilotmega)	3m 7s
test-embedded-size	39s
	38m 6s

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