Add a section on multi-container support for Serving

Add new section to the topic maps

Remove unnecessary step, improve description, minor fixes

Better phrasing

Author: rh-max

_topic_maps/_topic_map.yml

@@ -3845,6 +3845,8 @@ Topics:
     Topics:
     - Name: Overriding system deployment configurations
       File: overriding-config-serving
+    - Name: Multi-container support
+      File: multi-container-support-for-serving
     - Name: EmptyDir volumes
       File: empty-dir
     - Name: Persistent Volume Claims

_topic_maps/_topic_map_osd.yml

@@ -427,6 +427,8 @@ Topics:
     Topics:
     - Name: Overriding system deployment configurations
       File: overriding-config-serving
+    - Name: Multi-container support
+      File: multi-container-support-for-serving
     - Name: EmptyDir volumes
       File: empty-dir
     - Name: Persistent Volume Claims

_topic_maps/_topic_map_rosa.yml

@@ -622,6 +622,8 @@ Topics:
     Topics:
     - Name: Overriding system deployment configurations
       File: overriding-config-serving
+    - Name: Multi-container support
+      File: multi-container-support-for-serving
     - Name: EmptyDir volumes
       File: empty-dir
     - Name: Persistent Volume Claims

modules/serverless-configuring-multi-container-service.adoc

@@ -0,0 +1,34 @@
+// Module included in the following assemblies:
+//
+// * serverless/knative-serving/config-applications/multi-container-support-for-serving.adoc
+
+:_content-type: PROCEDURE
+[id="serverless-configuring-multi-container-service_{context}"]
+= Configuring a multi-container service
+
+Multi-container support is enabled by default. You can create a multi-container pod by specifiying multiple containers in the service.
+
+.Procedure
+
+. Modify your service to include additional containers. Only one container can handle requests, so specify `ports` for exactly one container. Here is an example configuration with two containers:
++
+.Multiple containers configuration
+[source,yaml]
+----
+apiVersion: serving.knative.dev/v1
+kind: Service
+...
+spec:
+  template:
+    spec:
+      containers:
+        - name: first-container <1>
+          image: gcr.io/knative-samples/helloworld-go
+          ports:
+            - containerPort: 8080 <2>
+        - name: second-container <3>
+          image: gcr.io/knative-samples/helloworld-java
+----
+<1> First container configuration.
+<2> Port specification for the first container.
+<3> Second container configuration.

serverless/knative-serving/config-applications/multi-container-support-for-serving.adoc

@@ -0,0 +1,13 @@
+:_content-type: ASSEMBLY
+include::_attributes/common-attributes.adoc[]
+[id="multi-container-support-for-serving"]
+= Multi-container support for Serving
+:context: multi-container-support-for-serving
+
+You can deploy a multi-container pod by using a single Knative service. This method is useful for separating application responsibilities into smaller, specialized parts.
+
+:FeatureName: Multi-container support for Serving
+include::snippets/technology-preview.adoc[leveloffset=+2]
+
+// Multi-container support
+include::modules/serverless-configuring-multi-container-service.adoc[leveloffset=+1]