fix(deploy): copy .npmrc before npm ci in frontend Dockerfile

Production deploy has been broken since the Next.js migration merged:
the Dockerfile ran `npm ci` right after COPY package*.json, before the
later `COPY . .` that would bring in .npmrc -- so the legacy-peer-deps
fix for react-scripts' stale TS ^4 peer constraint (added for CI in
dbb1580) never took effect in the actual deploy image, and every
deploy since has failed with the same ERESOLVE error CI hit before
that fix. Copy .npmrc alongside package*.json so npm ci sees it.

job-tracker-ui/Dockerfile

@@ -8,7 +8,7 @@ ARG NEXT_PUBLIC_API_BASE_URL
 ENV NEXT_PUBLIC_GOOGLE_CLIENT_ID=$NEXT_PUBLIC_GOOGLE_CLIENT_ID
 ENV NEXT_PUBLIC_API_BASE_URL=$NEXT_PUBLIC_API_BASE_URL
 
-COPY package*.json ./
+COPY package*.json .npmrc ./
 RUN npm ci
 
 COPY . .