Docs: Add release instructions (#115)

Author: kevinwcyu

CONTRIBUTING.md

@@ -0,0 +1,14 @@
+# Contributing to sqlds
+
+## Releasing
+
+If you want to create a new version of the sqlds for release, follow these steps:
+
+- Checkout the commit you want to tag (`git checkout <COMMIT_SHA>`)
+- Run `git tag <VERSION>` (For example **v3.3.0**)
+  - NOTE: We're using Lightweight Tags, so no other options are required
+- Run `git push origin <VERSION>`
+- Verify that the tag was create successfully [here](https://github.com/grafana/sqlds/tags)
+- Create a release from the tag on GitHub.
+  - Use the tag name as title.
+  - Click on the _Generate release notes_ button.