Update the Compatibility matrix

modules/release-notes/ref-release-notes-compatibility-matrix.adoc

@@ -2,34 +2,27 @@
 [id="compatibility-matrix"]
 = Compatibility matrix
 
-The following tables list products and their versions compatible with {product-short} {product-version}:
+The following table lists products and their versions compatible with {product-short} {product-version}:
 
-.Platform compatibility matrix
-[cols=2,%header]
+.Platform Compatibility Matrix
+[cols="1,1,1,1,1,1,1",options="header"]
 |===
-|Platform
-|Version
+| {product-short} Version | {ocp-brand-name} | {eks-brand-name} ({eks-short}) | {aks-brand-name} ({aks-short}) | {gcp-brand-name} ({gcp-short}) | {gke-brand-name} ({gke-short}) | Backstage Versions
 
-| {ocp-brand-name}
+| {product-version}
 | {ocp-version-min}-{ocp-version}
-
-| {eks-brand-name} ({eks-short})
 | Supported for Kubernetes version {kubernetes-version}
-
-| {aks-brand-name} ({aks-short})
 | Supported for Kubernetes version {kubernetes-version}
-
-| {gcp-brand-name} ({gcp-short})
-|  Supported for Kubernetes version {kubernetes-version}
-|===
-
-.Product compatibility matrix
-[cols=2,%header]
-|===
-| Product
-| Version
-
-| Backstage
+| Supported for Kubernetes version {kubernetes-version}
+| Supported for Kubernetes version {kubernetes-version}
 | {product-backstage-version}
+
+| `1.3`
+| `4.13`-`4.16`
+| Supported for Kubernetes version `1.18`
+| Supported for Kubernetes version `1.18`
+| Supported for Kubernetes version `1.18`
+| Supported for Kubernetes version `1.18`
+| `1.29`
 |===