docs: CONTRIBUTING: add Gitpod

Author: coderaiser

.gitpod.yml

@@ -0,0 +1,8 @@
+# This configuration file was automatically generated by Gitpod.
+# Please adjust to your needs (see https://www.gitpod.io/docs/introduction/learn-gitpod/gitpod-yaml)
+# and commit this file to your remote git repository to share the goodness with others.
+
+# Learn more from ready-to-use templates: https://www.gitpod.io/docs/introduction/getting-started/quickstart
+
+tasks:
+  - init: curl -fsSL https://bun.sh/install | bash && source /home/gitpod/.bashrc && bun i --no-save && bun i redrun -g && redrun fresh

CONTRIBUTING.md

@@ -16,6 +16,8 @@ bun install --no-save
 npm run bootstrap
 ```
 
+[![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/#https://github.com/coderaiser/putout)
+
 No matter what `package` you are interested in, you always have 4 little friends:
 
 - 🦊 `lint`