fix(platform-server): Resolve absolute URL from baseUrl (#39334)

This commit fixes a bug when `useAbsoluteUrl` is set to true and
`ServerPlatformLocation` infers the base url from the supplied
`url`. User should explicitly set the `baseUrl` when they turn on
`useAbsoluteUrl`.

Breaking change:
If you use `useAbsoluteUrl` to setup `platform-server`, you now need to
also specify `baseUrl`.
We are intentionally making this a breaking change in a minor release,
because if `useAbsoluteUrl` is set to `true` then the behavior of the
application could be unpredictable, resulting in issues that are hard to
discover but could be affecting production environments.

PR Close #39334

goldens/public-api/platform-server/platform-server.d.ts

@@ -3,6 +3,7 @@ export declare const BEFORE_APP_SERIALIZED: InjectionToken<(() => void | Promise
 export declare const INITIAL_CONFIG: InjectionToken<PlatformConfig>;
 
 export declare interface PlatformConfig {
+    baseUrl?: string;
     document?: string;
     url?: string;
     useAbsoluteUrl?: boolean;