Description of problem:
The oc-mirror result mapping.txt is not correct , can’t be used by `oc image mirror` command


Version-Release number of selected component (if applicable):
oc-mirror version 
Client Version: version.Info{Major:"", Minor:"", GitVersion:"4.11.0-202205131159.p0.g7bde4c7.assembly.stream-7bde4c7", GitCommit:"7bde4c7bde6b829a34592b2d12115fb38b15576f", GitTreeState:"clean", BuildDate:"2022-05-13T12:59:14Z", GoVersion:"go1.18", Compiler:"gc", Platform:"linux/amd64"}

How reproducible:
always

Steps to Reproduce:
1. Use oc-mirror with dry-run to create the mapping.txt :
cat setting.yaml 
kind: ImageSetConfiguration
apiVersion: mirror.openshift.io/v1alpha2
storageConfig:
  registry:
    skipTLS: false
    imageURL: xxxxx.us-east-2.compute.amazonaws.com:5000/test:latest
mirror:
  platform:
    channels:
    - name: stable-4.10
      type: ocp
  operators:
  - catalog: registry.redhat.io/redhat/redhat-operator-index:v4.11
    packages:
    - name: serverless-operator
      channels:
      - name: stable
  additionalImages:
  - name: registry.redhat.io/ubi8/ubi:latest
  helm: {}

`oc-mirror --config setting.yaml docker://xxxxx.us-east-2.compute.amazonaws.com:5000/test  --dry-run`

Check the result mapping.txt by `oc image mirror` command
Actual result:
2. Can’t use the result mapping.txt by `oc image mirror` command:
cat /tmp/mapping.txt 
quay.io/openshift-release-dev/ocp-v4.0-art-dev@sha256:63364747637b0e0b595e709e8192f3010240f08936be0370be0072bb4b447e43=ec2-18-119-110-153.us-east-2.compute.amazonaws.com:5000/test/openshift/release@sha256:63364747637b0e0b595e709e8192f3010240f08936be0370be0072bb4b447e43
quay.io/openshift-release-dev/ocp-v4.0-art-dev@sha256:487660f0e6fa0efea2c00793c52d3f0de228412732640dc07f7d3a0ab5139f48=ec2-18-119-110-153.us-east-2.compute.amazonaws.com:5000/test/openshift/release@sha256:487660f0e6fa0efea2c00793c52d3f0de228412732640dc07f7d3a0ab5139f48

……

oc image mirror  --filter-by-os '.*' -f /tmp/mapping.txt --max-per-registry 1  --skip-multiple-scopes=true
Warning: the default reading order of registry auth file will be changed from "${HOME}/.docker/config.json" to podman registry config locations in the future version of oc. "${HOME}/.docker/config.json" is deprecated, but can still be used for storing credentials as a fallback. See https://github.com/containers/image/blob/main/docs/containers-auth.json.5.md for the order of podman registry config locations.
error: file /tmp/mapping.txt, line 1: you must specify a tag for DST or leave it blank to only push by digest



Expected results:
Should create the correct format for mapping.txt and could be used by `oc image mirror` command.


Additional info:
The correct format for mapping.txt example:
cat manifests-ocp4-index-1652767008/mapping.txt 
registry.redhat.io/amq7/amq-streams-kafka-27-rhel8@sha256:dc9399239b3f06b6c2a020af25cf6be60d3931cb5ff3cb79b9f2e40075d2ad18=ec2-18-119-110-153.us-east-2.compute.amazonaws.com:5000/test/amq7-amq-streams-kafka-27-rhel8:8ed7fc5f
registry.stage.redhat.io/amq7/amqstreams-rhel7-operator-metadata@sha256:eaa66e127f03083033a3e64b2e9f08b8f1157440fdc0b7bf80cc62f1af24452e=ec2-18-119-110-153.us-east-2.compute.amazonaws.com:5000/test/amq7-amqstreams-rhel7-operator-metadata:53ce1f20
……