generate completions #649

Job	Run time
test-juliaup (x86_64-pc-windows-msvc)	6m 57s
test-juliaup (x86_64-pc-windows-gnu)	7m 55s
check-juliaup (x86_64-pc-windows-msvc-windowsstore)	2m 40s
test-juliaup (x86_64-apple-darwin)	6m 3s
check-juliaup (x86_64-pc-windows-msvc-windowsappinstaller)	2m 32s
test-juliaup (x86_64-unknown-linux-gnu)	3m 7s
check-juliaup (x86_64-pc-windows-gnu-msi)	3m 2s
test-juliaup (x86_64-unknown-linux-musl)	6m 1s
check-juliaup (x86_64-pc-windows-gnu-msi)	2m 58s
test-juliaup (i686-pc-windows-msvc)	5m 48s
check-juliaup (x86_64-apple-darwin)	1m 11s
test-juliaup (i686-pc-windows-gnu)	9m 26s
check-juliaup (x86_64-unknown-linux-gnu)	1m 46s
check-juliaup (x86_64-unknown-linux-musl)	1m 51s
check-juliaup (i686-pc-windows-msvc-windowsstore)	2m 38s
check-juliaup (i686-pc-windows-msvc-windowsappinstaller)	1m 45s
check-juliaup (i686-pc-windows-gnu-msi)	2m 53s
check-juliaup (i686-unknown-linux-gnu)	2m 46s
check-juliaup (i686-unknown-linux-musl)	1m 53s
check-juliaup (aarch64-unknown-linux-gnu)	1m 35s
check-juliaup (aarch64-unknown-linux-musl)	1m 57s
check-juliaup (aarch64-apple-darwin)	1m 33s
	1h 18m 17s

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