Add Dockerfile for Go web app

[Rupali-1003]

This PR adds a Dockerfile to the Go web app to enable easy containerization and deployment.

Changes included:

• Added Dockerfile for multi-stage build:
  • Builds Go binary inside golang:1.22.5 image
  • Copies static folder for serving HTML pages
  • Exposes port 8080
• Go app binds to 0.0.0.0:8080 to allow access from host/EC2
• Ready to run with:
  docker build -t go-web-app .
  docker run -p 8080:8080 go-web-app

Testing:

• Tested locally and on AWS EC2
• All routes (/home, /courses, /about, /contact) are serving the correct static HTML pages

This Dockerfile helps new contributors or deployers quickly run the app in a container without manual setup.

[Rupali-1003]

Hi! Added a Dockerfile to containerize the Go web app and serve static pages properly. Tested locally and on AWS EC2. Please review.