ci: fix @dependabot npm package-ecosystem x yarn integration

- https://docs.github.com/code-security/dependabot/dependabot-version-updates/configuration-options-for-the-dependabot.yml-file#npm-registry

Signed-off-by: Lexus Drumgold <unicornware@flexdevelopment.llc>

Author: unicornware

.yarnrc.yml

@@ -21,7 +21,7 @@ nodeLinker: node-modules
 npmScopes:
   flex-development:
     npmAlwaysAuth: true
-    npmAuthToken: ${GITHUB_TOKEN}
+    npmAuthToken: ${GITHUB_TOKEN:-$PAT_BOT}
     npmRegistryServer: https://npm.pkg.github.com
 
 patchFolder: ./patches