Add step in docker file for token

Dockerfile.playwright

@@ -5,6 +5,9 @@ FROM mcr.microsoft.com/playwright:v1.48.0-noble
 # Set the working directory in the container
 WORKDIR /app
 
+# Accept GitHub token as a build argument
+ARG GITHUB_TOKEN
+
 # Copy package.json and package-lock.json
 COPY package*.json ./
 
@@ -14,7 +17,8 @@ RUN npm install
 # Copy playwright-tests package files + authenticated .npmrc, then install
 COPY playwright-tests/package*.json ./playwright-tests/
 COPY playwright-tests/.npmrc ./playwright-tests/
-RUN cd playwright-tests && npm install
+RUN --mount=type=secret,id=GITHUB_TOKEN \
+    cd playwright-tests && GITHUB_TOKEN=$(cat /run/secrets/GITHUB_TOKEN) npm install
 
 # Install Playwright browsers
 RUN npx playwright install chromium --with-deps