feat(STONEINTG-892): update doc for override snapshot

* update doc to add snapshotComponent's source for override snapshot

Signed-off-by: Hongwei Liu <[email protected]>

docs/modules/ROOT/pages/how-to-guides/testing_applications/proc_creating_override_snapshot.adoc

@@ -32,10 +32,14 @@ spec:
   components:
     - name: component-sample <2>
       containerImage: quay.io/redhat-user-workloads/ws-sample-tenant/application-sample/component-sample@sha256:0db0a473a6abf5c15c424ab07cfbd5c40c06622fe648d4fe6a6b6abc224a0d0c <3>
+      source: <4>
+        git:
+          revision: fa8b89274a61ef0f1c257b7a84c37aa2ec844109
 ----
 <1> The label `test.appstudio.openshift.io/type: override` that indicates this is an `override` snapshot.
 <2> The component name you will reset its Global Candidate List.
 <3> The container image with valid digest you will reset the component <2> to.
+<4> Optional. The component source containing the git revision.
 
 
 . Save the .yaml file and add the snapshot.yaml by running the following command:
@@ -61,7 +65,7 @@ status: "True"
 type: AddedToGlobalCandidateList
 ----
 
-. Browse to the component you are updating and select the **Component details** tab. The updated container image is shown under **Image** column.
+. Browse to the component you are updating and select the **Component details** tab. The updated container image is shown under **Image** column. The updated source is shown under **Source code** column.
 
 . Check component's `.Spec.ContainerImage` by the following command:
 +
@@ -70,3 +74,11 @@ type: AddedToGlobalCandidateList
 $ oc get component component-sample -n ws-sample-tenant -o yaml | yq .spec.containerImage
 quay.io/redhat-user-workloads/ws-sample-tenant/application-sample/component-sample@sha256:0db0a473a6abf5c15c424ab07cfbd5c40c06622fe648d4fe6a6b6abc224a0d0c
 ----
+
+. Check component's `.Status.LastBuiltCommit` by the following command:
++
+[source,terminal]
+----
+$ oc get component component-sample -n ws-sample-tenant -o yaml | yq .status.lastBuiltCommit
+fa8b89274a61ef0f1c257b7a84c37aa2ec844109
+----