Create CONTRIBUTING.md file with develop branch guideline

[#92459188]

Signed-off-by: Colin Jackson <colin.s.jackson90@gmail.com>

Author: styeung

CONTRIBUTING.md

@@ -0,0 +1,12 @@
+# Contributing
+
+## Run the tests
+
+See the [Machete](https://github.com/cf-buildpacks/machete) CF buildpack test framework for more information.
+
+## Pull Requests
+
+1. Fork the project
+1. Submit a pull request
+
+**NOTE:** When submitting a pull request, *please make sure to target the `develop` branch*, so that your changes are up-to-date and easy to integrate with the most recent work on the buildpack. Thanks!