chore: update readme install cmd (#14)

Author: averikitsch

README.md

@@ -18,7 +18,7 @@ Learn more about [Gemini CLI Extensions](https://github.com/google-gemini/gemini
 
 Before you begin, ensure you have the following:
 
-* [Gemini CLI](https://github.com/google-gemini/gemini-cli) installed with version +v0.6.0.
+* [Gemini CLI](https://github.com/google-gemini/gemini-cli) installed with version **+v0.6.0**.
 * A Google Cloud project with the **Cloud SQL Admin API** enabled.
 * IAM Permissions:
   * Cloud SQL Client (`roles/cloudsql.client`)
@@ -29,7 +29,7 @@ Before you begin, ensure you have the following:
 To install the extension, use the command:
 
 ```bash
-gemini extensions install github.com/gemini-cli-extensions/cloud-sql-postgresql
+gemini extensions install https://github.com/gemini-cli-extensions/cloud-sql-postgresql
 ```
 
 ## Configuration