[ci] Lint on non-test code importing packages from /tests #6752

Job	Run time
e2e	10m 26s
Protobuf Lint	5s
Up-to-date mocks	2m 14s
Up-to-date protobuf	21s
e2e_existing_network	3m 37s
Fuzz	12m 58s
Up-to-date go.mod and go.sum	9s
Lint	3m 14s
Build Antithesis avalanchego images	5m 59s
Build Antithesis xsvm images	8m 21s
Image build	11m 8s
Unit (macos-12)	7m 39s
Upgrade	3m 17s
Unit (ubuntu-20.04)	6m 46s
Unit (ubuntu-22.04)	6m 42s
Unit (windows-2022)	11m 58s
Unit (custom-arm64-focal)	12m 38s
Unit (custom-arm64-jammy)	11m 38s
	1h 59m 10s

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