ci: cancel previous build on PR update #1921

Job	Run time
Code style	40s
build-integration	4m 3s
Build (C9S)	1m 38s
Build (Fedora)	1m 21s
Build - FCOS minimal	1m 42s
Debian Stable with sign-ed25519 and FUSE 2	7m 35s
Debian Stable with curl, sign-ed25519, no gpgme, FUSE 3	6m 57s
Debian Stable 32 bit	7m 45s
Debian Stable without libsystemd	7m 15s
Debian Testing	7m 45s
Debian Testing with libsoup3	7m 3s
Debian stable + static-prepareroot	7m 17s
Ubuntu Latest Release	7m 5s
Privileged testing	49s
	1h 8m 55s

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