Fixed issue with Web Docker image not getting proper environment variable substitution

As ReactJS does not seem to support reading environment variables from Docker runtime variables, we'll pull it instead from buildtime.
Also added copying of nginx config file in the Dockerfile
Modified API Dockerfile to accept WebUri for CORS, also removed duplicate setting of CORS in Program.cs

Web/Dockerfile

@@ -1,22 +1,15 @@
 FROM node:17-alpine as builder
 
 # Set the environment variables
-ENV API_BASE_URL=
-ENV AUTH0_DOMAIN=
-ENV AUTH0_CLIENT_ID=
-ENV AUTH0_CALLBACK_URL=
-ENV AUTH0_AUDIENCE=
+ARG REACT_APP_API_BASE_URL
+ARG REACT_APP_AUTH0_DOMAIN
+ARG REACT_APP_AUTH0_CLIENT_ID
+ARG REACT_APP_AUTH0_CALLBACK_URL
+ARG REACT_APP_AUTH0_AUDIENCE
 
 WORKDIR /app
 COPY package.json  .
 RUN npm install
-
-RUN echo 'DEBUG': $API_BASE_URL
-RUN echo 'DEBUG': $AUTH0_DOMAIN
-RUN echo 'DEBUG': $AUTH0_CLIENT_ID
-RUN echo 'DEBUG': $AUTH0_CALLBACK_URL
-RUN echo 'DEBUG': $AUTH0_AUDIENCE
-
 COPY . .
 RUN npm run build
 
@@ -24,5 +17,6 @@ FROM nginx:mainline-alpine
 WORKDIR /usr/share/nginx/html
 RUN rm -rf ./*
 COPY --from=builder /app/build .
+COPY nginx.conf /etc/nginx/conf.d/default.conf
 EXPOSE 80
 ENTRYPOINT ["nginx", "-g", "daemon off;"]