Disable beta ecosystems for dependabot (#221)

Author: m-fila

.github/dependabot.yml

@@ -4,7 +4,6 @@
 # https://docs.github.com/github/administering-a-repository/configuration-options-for-dependency-updates
 
 version: 2
-enable-beta-ecosystems: true
 updates:
   # Keep dependencies for GitHub Actions up-to-date
   - package-ecosystem: 'github-actions'