docs: use repository URL in Docker build examples

Replace local folder building with direct link to repo master branch.

PR: ericc-ch#172

Author: jacks0n

README.md

@@ -64,7 +64,7 @@ bun install
 Build image
 
 ```sh
-docker build -t copilot-api .
+docker build -t copilot-api https://github.com/jacks0n/copilot-api.git#master
 ```
 
 Run the container
@@ -88,7 +88,7 @@ You can pass the GitHub token directly to the container using environment variab
 
 ```sh
 # Build with GitHub token
-docker build --build-arg GH_TOKEN=your_github_token_here -t copilot-api .
+docker build --build-arg GH_TOKEN=your_github_token_here -t copilot-api https://github.com/jacks0n/copilot-api.git#master
 
 # Run with GitHub token
 docker run -p 4141:4141 -e GH_TOKEN=your_github_token_here copilot-api