Update dependabot.yml file naming information

Clarified that the dependabot configuration file can be named dependabot.yaml in addition to dependabot.yml.

References:
- dependabot/feedback#874
- https://github.com/yaml/go-yaml/blob/main/.github/dependabot.yaml

Author: DanGM96

content/code-security/concepts/supply-chain-security/about-the-dependabot-yml-file.md

@@ -46,7 +46,7 @@ The `dependabot.yml` file controls how {% data variables.product.prodname_depend
 
 ## Where to store the `dependabot.yml` file
 
-You must store this file in the `.github` directory of your repository in the default branch (typically `main`). The path is:  `.github/dependabot.yml`.
+You must store this file in the `.github` directory of your repository in the default branch (typically `main`). The path is:  `.github/dependabot.yml` (you can also use `.github/dependabot.yaml`).
 
 ## How the `dependabot.yml` file works