Updating docs to include IKS in various places (#10047)

* Change product name

From IBM Cloud Container Service to IBM Cloud Kubernetes Service

* Adding IKS to the table of solutions

Not sure about where in the table it should be placed. The note said,
“The above table is ordered by version test/used in nodes, followed by
support level.”

* Adding IKS to Cloud Providers page

* Adding IBM Cloud Container Registry to private registry topic

* Updating language on cloud provider page

* Revising text for the registry entry

* Specifying that it's calico network policies

content/en/includes/partner-script.js

@@ -831,7 +831,7 @@
 			name: 'IBM',
 			logo: 'ibm',
 			link: 'https://www.ibm.com/cloud/container-service',
-			blurb: 'IBM - IBM Cloud Container Service'
+			blurb: 'IBM - IBM Cloud Kubernetes Service'
 				},
 		{
 			type: 2,