Continuous Integration With GitHub Actions

TODO: File a subtask under HDDS-9861 and complete this page or section.

Aggregate content from our various GitHub actions guides, including

• ci.md
• CONTRIBUTING.md
• https://cwiki.apache.org/confluence/display/OZONE/Ozone+CI+with+Github+Actions
• https://cwiki.apache.org/confluence/display/OZONE/Github+Actions+tips+and+tricks.