build-test

Add Alpine 3.20 variant #726

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Run time

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Job	Run time
generate-matrix	5s
generate-matrix	5s
build (18.20.3, alpine3.20)	3s
build (18.20.3, alpine3.20)	22s
build (20.13.1, alpine3.20)	4s
build (20.13.1, alpine3.20)	23s
build (21.7.3, alpine3.20)	11s
build (21.7.3, alpine3.20)	19s
build (22.2.0, alpine3.20)	8s
build (22.2.0, alpine3.20)	20s
build (18.20.3, alpine3.20)	7s
build (18.20.3, alpine3.20)	19s
build (20.13.1, alpine3.20)	7s
build (20.13.1, alpine3.20)	15s
build (21.7.3, alpine3.20)	8s
build (21.7.3, alpine3.20)	17s
build (22.2.0, alpine3.20)	12s
build (22.2.0, alpine3.20)	19s
	3m 44s