refactor(@angular-devkit/build-angular): use type imports for @angular/compiler-cli peer dependency

The `@angular/compiler-cli` is used as a peer dependency and has the potential to not be present. As a result static imports should only be used for types and value imports should be dynamic so that they can be guarded in the event of package absence. There are still several instances of static imports for values but these will be corrected in follow-ups.

Author: clydin

packages/angular_devkit/build_angular/src/utils/build-options.ts

@@ -7,7 +7,7 @@
  */
 
 import { logging } from '@angular-devkit/core';
-import { ParsedConfiguration } from '@angular/compiler-cli';
+import type { ParsedConfiguration } from '@angular/compiler-cli';
 import {
   AssetPatternClass,
   Budget,

packages/angular_devkit/build_angular/src/utils/read-tsconfig.ts

@@ -6,7 +6,7 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import { ParsedConfiguration } from '@angular/compiler-cli';
+import type { ParsedConfiguration } from '@angular/compiler-cli';
 import * as path from 'path';
 
 /**

packages/angular_devkit/build_angular/src/webpack/configs/typescript.ts

@@ -7,7 +7,7 @@
  */
 
 import { getSystemPath } from '@angular-devkit/core';
-import { CompilerOptions } from '@angular/compiler-cli';
+import type { CompilerOptions } from '@angular/compiler-cli';
 import { AngularWebpackLoaderPath, AngularWebpackPlugin } from '@ngtools/webpack';
 import { ScriptTarget } from 'typescript';
 import { Configuration } from 'webpack';