How-to video embed-links for Astra DB and MongoDB connectors (#287)

Author: Paul-Cornell

snippets/general-shared-text/astradb.mdx

@@ -1,5 +1,15 @@
 The Astra DB connector prerequisites:
 
+<iframe
+width="560"
+height="315"
+src="https://www.youtube.com/embed/kupQrnCQjPw"
+title="YouTube video player"
+frameborder="0"
+allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture"
+allowfullscreen
+></iframe>
+
 - An Astra account. [Create or sign in to an Astra account](https://astra.datastax.com/).
 - A database in the Astra account. [Create a database in an account](https://docs.datastax.com/en/astra-db-classic/databases/manage-create.html).
 - An application token for the database. [Create a database application token](https://docs.datastax.com/en/astra-db-serverless/administration/manage-application-tokens.html).