update dbm mongodb beta installation script to include guides to DD_S…

…ITE (#24317)

layouts/shortcodes/dbm-mongodb-agent-beta-install-docker.md

@@ -1,9 +1,14 @@
 To install the beta version of the containerized Datadog Agent, run the following command.
+Replace `<DD_API_KEY>` with your [Datadog API key][1] and `<DD_SITE>` with your [Datadog site][2].
 
 ```shell
 # Override the following environment variables
 export DD_API_KEY=<DD_API_KEY>
+export DD_SITE=<DD_SITE>
 export DD_AGENT_VERSION=7.56.0-dbm-mongo-1.3
 
 docker pull "datadog/agent:${DD_AGENT_VERSION}"
 ```
+
+[1]: /account_management/api-app-keys/
+[2]: /getting_started/site/

layouts/shortcodes/dbm-mongodb-agent-beta-install-kubernetes.md

@@ -1,8 +1,10 @@
 To install the beta version of the Datadog Agent on Kubernetes, run the following command.
+Replace `<DD_API_KEY>` with your [Datadog API key][1] and `<DD_SITE>` with your [Datadog site][2].
 
 ```shell
 # Override the following environment variables
 export DD_API_KEY=<DD_API_KEY>
+export DD_SITE=<DD_SITE>
 
 helm repo add datadog https://helm.datadoghq.com
 helm repo update
@@ -21,3 +23,5 @@ datadog:
 
 ```
 
+[1]: /account_management/api-app-keys/
+[2]: /getting_started/site/

layouts/shortcodes/dbm-mongodb-agent-beta-install-linux.md

@@ -1,4 +1,5 @@
 To install the beta version of the Datadog Agent on a Linux host, run the following command.
+Replace `<DD_API_KEY>` with your [Datadog API key][1] and `<DD_SITE>` with your [Datadog site][2].
 
 ```shell
 # Override the following environment variables
@@ -7,5 +8,8 @@ export DD_AGENT_DIST_CHANNEL=beta
 export DD_AGENT_MAJOR_VERSION=7
 export DD_AGENT_MINOR_VERSION="56.0~dbm~mongo~1.3"
 
-DD_API_KEY=<DD_API_KEY> DD_SITE="datadoghq.com" bash -c "$(curl -L https://install.datadoghq.com/scripts/install_script_agent7.sh)"
+DD_API_KEY=<DD_API_KEY> DD_SITE=<DD_SITE> bash -c "$(curl -L https://install.datadoghq.com/scripts/install_script_agent7.sh)"
 ```
+
+[1]: /account_management/api-app-keys/
+[2]: /getting_started/site/