.gitignoring file called 'changes' that's produced and consumed by goreleaser

[jkremser]

This entry was removed from the .gitignore recently, but it needs to be there for the release process to finish w/o errors.

We create the file here: https://github.com/k8gb-io/k8gb/blob/master/.github/workflows/release.yaml#L27

and consume it within the same action couple of steps later here: https://github.com/k8gb-io/k8gb/blob/master/.github/workflows/release.yaml#L49

But if it's not ignored, the goreleaser fails on this issue: https://github.com/k8gb-io/k8gb/runs/4372363917?check_suite_focus=true#step:8:23
because the git is in dirty state (there are untracked files). Other workaround would be copying that file somewhere else on that filesystem, but it's imho better to .gitignore it as it was before.

Signed-off-by: Jirka Kremser [email protected]

[jkremser]

upgrade testing will be failing until the release is reverted (the 0.8.5 tag is there in the git repo, but container image is not there on dockerhub)