tests: new 'tests-monthly' branch to automate detection of unmaintained projects, syntax errors, broken links

'master' will be merged in this branch on a schedule/periodically to trigger checks against the latest list
It does not make sent to run the full URL test suite at every commit on master
This also allows to generate the badge at https://github.com/Kickball/awesome-selfhosted/issues/1767 (and on the main page) which will be auto-updated

.travis.yml

@@ -1,20 +1,10 @@
-language: node_js
-
-node_js:
-  - "node"
+language: ruby
 
 before_install:
-  - rvm install 2.6.2
   - gem install awesome_bot
-  - gem install danger
-
-before_script:
 
 script:
-  - git diff master.. --unified=0 README.md | grep --perl-regexp --only-matching --silent "(?<=^\+).*" >> temp.md || (exit 0)
-  - node tests/test.js temp.md
-  - awesome_bot temp.md --allow-redirect || (exit 0)
-  - danger --dangerfile=tests/Dangerfile --verbose
+  - make monthly
 
 notifications:
   email: false