[serverless] Add section for container image setup for Go (#16214)

* add section for container image setup for Go

* fix

Author: DylanLovesCoffee

content/en/serverless/installation/go.md

@@ -54,6 +54,26 @@ For more information and additional settings, see the [plugin documentation][1].
 [3]: https://docs.datadoghq.com/getting_started/site/
 [4]: https://app.datadoghq.com/organization-settings/api-keys
 {{% /tab %}}
+{{% tab "Container Image" %}}
+
+1. Install the Datadog Lambda Extension
+
+    ```dockerfile
+    COPY --from=public.ecr.aws/datadog/lambda-extension:<TAG> /opt/. /opt/
+    ```
+
+    Replace `<TAG>` with either a specific version number (for example, `{{< latest-lambda-layer-version layer="extension" >}}`) or with `latest`. You can see a complete list of possible tags in the [Amazon ECR repository][1].
+
+2. Set the required environment variables
+
+    - Set `DD_SITE` to {{< region-param key="dd_site" code="true" >}} (ensure the correct SITE is selected on the right).
+    - Set `DD_API_KEY_SECRET_ARN` to the ARN of the AWS secret where your [Datadog API key][2] is securely stored. The key needs to be stored as a plaintext string (not a JSON blob). The `secretsmanager:GetSecretValue` permission is required. For quick testing, you can use `DD_API_KEY` instead and set the Datadog API key in plaintext.
+    - Optionally set `DD_UNIVERSAL_INSTRUMENTATION: true` to take advantage of [advanced configurations][3] such as capturing the Lambda request and response payloads and inferring APM spans from incoming Lambda events.
+
+[1]: https://gallery.ecr.aws/datadog/lambda-extension
+[2]: https://app.datadoghq.com/organization-settings/api-keys
+[3]: /serverless/configuration/
+{{% /tab %}}
 {{% tab "Custom" %}}
 ### Install the Datadog Lambda Extension