Use ALB URL rewrite instead of ArcGIS Web Adaptor in AWS templates

The main reason why ArcGIS Web Adaptor is configurable web context path. This allows multiple deployments using the same load balancer and same port. Fronting deployments with Web Adaptor, though, has many disadvantages:

- Requires to install/configure and update/upgrade Web Servers (IIS, Apache Tomcat) and their dependencies (OpenJDK)
- Adds web response latency because of extra cross-process call
- Increases deployment time (in particular, configuring WA with portal may take 10+ minutes)
- Complicates security

AWS Application Load Balancer now supports [URL and host header rewrite](https://aws.amazon.com/about-aws/whats-new/2025/10/application-load-balancer-url-header-rewrite/), which can be used to change the deployments' context path.

All the AWS deployment templates should be modified to use ALB URL rewrite instead of Web Adaptor.

See: https://enterprise.arcgis.com/en/server/latest/deploy/linux/using-a-reverse-proxy-server-with-arcgis-server.htm