OCPBUGS#19016: Text snippet for Operator groups name

The text snippet in this PR only applies to branches 4.11-4.14.
In order to keep the text snippets folder in sync and to avoid
future merge conflicts, the work of adding the snippet to the repo
and placing the content in the documentation is broken up.

This PR creates the snippet. #64754 adds the snippet to appropriate
content. Please see #64754 for QE and SME acks.

snippets/operator-group-unique-name.adoc

@@ -0,0 +1,15 @@
+// Text snippet included in the following assemblies:
+//
+
+:_mod-docs-content-type: SNIPPET
+
+[WARNING]
+====
+Operator Lifecycle Manager (OLM) creates the following cluster roles for each Operator group:
+
+* `<operatorgroup_name>-admin`
+* `<operatorgroup_name>-edit`
+* `<operatorgroup_name>-view`
+
+When you manually create an Operator group, you must specify a unique name that does not conflict with the existing cluster roles or other Operator groups on the cluster.
+====