docs: sharpen the instructions for creating/update oauthclient

Signed-off-by: Zvi Grinberg <[email protected]>

Author: zvigrinberg

kustomize/README.md

@@ -115,13 +115,16 @@ EOF
 
 5. Create the `oauth-secret.env` file containing the `client-secret` and `openshift-domain` values required by the [ExploitIQ Client](./base/exploit_iq_client.yaml) configuration.
 
-Replace `some-long-secret-used-by-the-oauth-client` with a more secure, unique secret
+If openshift resource of kind `OAuthClient` named `exploit-iq-client` exists, just get the secret from there:
+```shell
+export OAUTH_CLIENT_SECRET=$(oc get oauthclient exploit-iq-client -o jsonpath='{..secret}')
+```
+Otherwise, Replace `some-long-secret-used-by-the-oauth-client` with a more secure, unique secret of your own:
 
 ```shell
 export OAUTH_CLIENT_SECRET="some-long-secret-used-by-the-oauth-client"
 ```
 
-
 ```shell
 cat > base/oauth-secrets.env << EOF
 client-secret=$OAUTH_CLIENT_SECRET
@@ -168,7 +171,7 @@ redirectURIs:
   - "http://$(oc get route exploit-iq-client -o jsonpath='{.spec.host}')/app/index.html"
 EOF
 ```
-Otherwise, just add your route to the existing `OAuthClient` CR object:
+Otherwise ( if creating `OAuthClient` instance got error because it's already exists in the cluster) , just add your route to the existing `OAuthClient` CR object:
 ```shell
 export HTTPS_ROUTE=https://$(oc get route exploit-iq-client -o jsonpath='{.spec.host}')/app/index.html
 export HTTP_ROUTE=http://$(oc get route exploit-iq-client -o jsonpath='{.spec.host}')/app/index.html