Update Documentation for UBI
Now that the RHEL images have been replaced by UBI as of version 4.2.2 of
the PostgreSQL Operator, this commit replaces all applicable references
to 'RHEL' in the PostgreSQL Operator documentation with 'UBI'.
@@ -74,11 +74,17 @@ dependency between the two projects at a specific version level.
## Operating Systems
The Operator is developed on both Centos 7 and RHEL 7 operating systems. The
-underlying containers are designed to use either Centos 7 or RHEL 7 as the base
-container image.
+underlying containers are designed to use either Centos 7 or Red Hat UBI 7 as
+the base container image.
Other Linux variants are possible but are not supported at this time.
+Also, please note that as of version 4.2.2 of the PostgreSQL Operator, Red Hat Univeral Base
+Image (UBI) 7 has replaced RHEL 7 as the base container image for the various PostgreSQL Operator
+containers. For more information on Red Hat UBI, please see the following link:
+
+https://www.redhat.com/en/blog/introducing-red-hat-universal-base-image
+
## Kubernetes Distributions
The Operator is designed and tested on Kubernetes and Openshift Container Platform.
