Revert "doc-2005: remove tech preview from EDGE API (#7278)" (#7279)

This reverts commit 42eceab.

Author: Linus-SpectroCloud

docs/api-content/api-docs/1-introduction.md

@@ -269,6 +269,10 @@ using embedded cluster definitions.
 You can find the Open API Swagger specification for the Edge Management API at the following location:
 https://raw.githubusercontent.com/spectrocloud/librarium/version-4-4/docs/api-content/api-docs/edge-v1/emc-api.json
 
+:::preview
+
+:::
+
 ### Authentication
 
 Use the `POST /v1/users/default/login` endpoint to generate an authentication token with your OS username and password.