Add .rustfmt.toml #605

Job	Run time
test-juliaup (x86_64-pc-windows-msvc)	7m 7s
test-juliaup (x86_64-pc-windows-gnu)	8m 40s
test-juliaup (x86_64-apple-darwin)	7m 36s
test-juliaup (x86_64-unknown-linux-gnu)	4m 51s
test-juliaup (x86_64-unknown-linux-musl)	5m 53s
test-juliaup (i686-pc-windows-msvc)	9m 4s
test-juliaup (i686-pc-windows-gnu)	14m 32s
check-juliaup (x86_64-pc-windows-msvc-windowsstore)	2m 55s
check-juliaup (x86_64-pc-windows-msvc-windowsappinstaller)	3m 40s
check-juliaup (x86_64-pc-windows-gnu-msi)	3m 29s
check-juliaup (x86_64-pc-windows-gnu-msi)	3m 9s
check-juliaup (x86_64-apple-darwin)	1m 36s
check-juliaup (x86_64-unknown-linux-gnu)	2m 31s
check-juliaup (x86_64-unknown-linux-musl)	2m 31s
check-juliaup (i686-pc-windows-msvc-windowsstore)	3m 1s
check-juliaup (i686-pc-windows-msvc-windowsappinstaller)	3m 11s
check-juliaup (i686-pc-windows-gnu-msi)	3m 13s
check-juliaup (i686-unknown-linux-gnu)	2m 20s
check-juliaup (i686-unknown-linux-musl)	3m 19s
check-juliaup (aarch64-unknown-linux-gnu)	2m 38s
check-juliaup (aarch64-unknown-linux-musl)	2m 32s
check-juliaup (aarch64-apple-darwin)	1m 34s
	1h 39m 22s

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