build: enable bundle_dts for a number of packages (#28726)

This change enables dts bundling for the following packages and their secondary entry points:

- @angular/animations
- @angular/elements
- @angular/http
- @angular/platform-browser
- @angular/platform-browser-dynamic
- @angular/platform-server
- @angular/platform-webworker
- @angular/platform-webworker-dynamic
- @angular/servce-worker

Dts bundling happens in `ng_module` bazel definition, hence packages such as `@angular/compiler`, `@angular/compiler-cli` and `@angular/langauge service` cannot be flattened as they use `ts_library`.

`@angular/core`, `@angular/common`, `@angular/upgrade` and `@angular/forms` will be done seperatly as it requires some changes either to their source or specs.

PR Close #28726

packages/platform-webworker-dynamic/BUILD.bazel

@@ -10,6 +10,7 @@ ng_module(
             "src/**/*.ts",
         ],
     ),
+    bundle_dts = True,
     deps = [
         "//packages:types",
         "//packages/common",