add one more step

CONTRIBUTING.md

@@ -6,8 +6,15 @@
 1. Fork the repository on GitHub
 2. Clone the forked repository to your local machine
 3. Build the frontend: `cd ui && npm build build`
-3. Install the project: `go install ./...`
-4. Run the project: `gocert --config config.yaml`
+4. Install the project: `go install ./...`
+5. Create a `config.yaml` file:
+```yaml
+keypath:  "./key.pem"
+certpath: "./cert.pem"
+dbpath: "./certs.db"
+port: 3000
+```
+6. Run the project: `gocert --config config.yaml`
 
 Commands for go need to be run from the project directory, and commands for the frontend need to be run from the `ui/` directory
 ## Testing