Update ability to filter helm charts when multiple Helm repos are available

Dev Epic: https://issues.redhat.com/browse/RHDEVDOCS-2333

We have docs here: https://docs.openshift.com/container-platform/4.6/cli_reference/helm_cli/configuring-custom-helm-chart-repositories.html .

Add a screenshot under step 2 and a point about being able to filter from console and select the reqd Helm Chart.

Please see comment by Serena here and add appropriate note/paragraph to this: https://issues.redhat.com/browse/ODC-2994?focusedCommentId=15377568&page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel#comment-15377568