ci: fix tests #544

Job	Run time
act-support (ubuntu-latest)	1m 47s
flakes (ubuntu-latest)	44s
extra-nix-config (ubuntu-latest)	28s
custom-nix-path (ubuntu-latest)	27s
flakes (macos-latest)	1m 35s
extra-nix-config (macos-latest)	1m 16s
installer-options (ubuntu-latest)	27s
custom-nix-path (macos-latest)	1m 33s
flakes (macos-13)	2m 24s
extra-nix-config (macos-13)	2m 37s
custom-nix-path (macos-13)	2m 23s
installer-options (macos-13)	2m 11s
oldest-supported-installer (ubuntu-latest)	22s
simple-build (ubuntu-latest)	30s
oldest-supported-installer (macos-latest)	1m 10s
simple-build (macos-latest)	1m 24s
oldest-supported-installer (macos-13)	1m 28s
simple-build (macos-13)	3m 5s
	25m 51s

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