cmd/go: go 1.22.0: go test throws errors when processing folders not listed in coverpkg argument [1.22 backport]

[gopherbot]

@thanm requested issue #65653 to be considered for backport to the next 1.22 minor release.

@gopherbot please consider this for backport to 1.22

[gopherbot]

Change https://go.dev/cl/569575 mentions this issue: cmd/go: respect -coverpkg for unselected no-test packages

[gopherbot]

Closed by merging 35b1a14 to release-branch.go1.22.