Allow jRuby to update via dependabot (#305)

Author: abelsromero

.github/dependabot.yml

@@ -7,7 +7,6 @@ updates:
     labels:
       - "dependencies"
     ignore:
-      - dependency-name: "org.jruby:jruby"
       - dependency-name: "com.googlecode.maven-download-plugin:download-maven-plugin"
   - package-ecosystem: "github-actions"
     directory: "/"