testing/*: put fish completions in correct place

testing/apmpkg/APKBUILD

testing/atlas/APKBUILD

testing/buf/APKBUILD

testing/cilium-cli/APKBUILD

testing/cue-cli/APKBUILD

testing/dapr-cli/APKBUILD

testing/ddgr/APKBUILD

testing/driftctl/APKBUILD

testing/elektra/APKBUILD

testing/exaile/APKBUILD

testing/exercism/APKBUILD

testing/ffsend/APKBUILD

testing/flameshot/APKBUILD

testing/flux/APKBUILD

testing/glow/APKBUILD

testing/golangci-lint/APKBUILD

testing/halp/APKBUILD

testing/helmfile/APKBUILD

testing/hub/APKBUILD

testing/hubble-cli/APKBUILD