build: switch coercion and keycodes entry-point to ng_module

We can't use "ts_library" for entry-points which should be part
of a "ng_package". This is because "ng_package" currently only
partially includes "ts_library" targets in the package (i.e. missing
`package.json` file for secondary entry-points).

Until we figure out what best practice is, or if angular/angular#32610
is merged, we just use "ng_module" to work around this issue.

src/cdk/coercion/BUILD.bazel

@@ -1,17 +1,14 @@
 package(default_visibility = ["//visibility:public"])
 
-load("//tools:defaults.bzl", "karma_web_test_suite", "markdown_to_html", "ts_library")
+load("//tools:defaults.bzl", "karma_web_test_suite", "markdown_to_html", "ng_module", "ts_library")
 
-ts_library(
+ng_module(
     name = "coercion",
     srcs = glob(
         ["**/*.ts"],
         exclude = ["**/*.spec.ts"],
     ),
     module_name = "@angular/cdk/coercion",
-    deps = [
-        "@npm//@angular/core",
-    ],
 )
 
 ts_library(

src/cdk/keycodes/BUILD.bazel

@@ -1,8 +1,8 @@
 package(default_visibility = ["//visibility:public"])
 
-load("//tools:defaults.bzl", "karma_web_test_suite", "markdown_to_html", "ts_library")
+load("//tools:defaults.bzl", "karma_web_test_suite", "markdown_to_html", "ng_module", "ts_library")
 
-ts_library(
+ng_module(
     name = "keycodes",
     srcs = glob(
         ["**/*.ts"],