Add Mulit Arch support of Manual Approval Gate

[Basavaraju-G]

as of now images of manual approval gate are not multi arch. need to Enable CI to build multi arch images

/manual-approval-gate# oc get pods -n tekton-pipelines
NAME                                               READY   STATUS             RESTARTS      AGE
manual-approval-gate-controller-797b668ffd-92hlf   0/1     CrashLoopBackOff   4 (39s ago)   2m15s
manual-approval-gate-webhook-7bb6fc877c-4b7nb      0/1     CrashLoopBackOff   4 (45s ago)   2m15s
tekton-events-controller-744496c748-fdzlg          1/1     Running            0             57s
tekton-pipelines-controller-67795468b5-vlpsc       1/1     Running            0             57s
tekton-pipelines-webhook-7cffbffd66-bwdcj          1/1     Running            0             57s
root@basavarg-buildvm-temp:~/go/src/github.com/openshift-pipelines/manual-approval-gate# oc logs manual-approval-gate-controller-797b668ffd-92hlf  -n tekton-pipelines
exec /ko-app/controller: exec format error
root@basavarg-buildvm-temp:~/go/src/github.com/openshift-pipelines/manual-approval-gate# oc logs manual-approval-gate-webhook-7bb6fc877c-4b7nb  -n tekton-pipelines
exec /ko-app/webhook: exec format error
root@basavarg-buildvm-temp:~/go/src/github.com/openshift-pipelines/manual-approval-gate#
root@basavarg-buildvm-temp:~/go/src/github.com/openshift-pipelines/manual-approval-gate#

[Basavaraju-G]

/assign @Basavaraju-G

[Basavaraju-G]

Raised PR for this feature #171