fix(language-service): Clear caches when program changes (#21337)

This commit fixes a bug whereby the caches are not cleared when the
program changes. This subsequently produces the incorrect error of
'Component ... is not included in a module ...'.

PR Close #19405

PR Close #21337

packages/language-service/test/diagnostics_spec.ts

@@ -248,7 +248,7 @@ describe('diagnostics', () => {
           template: \`
             <div *ngIf="comps | async; let comps; else loading">
             </div>
-            <ng-template #loading>Loading comps...</ng-template>            
+            <ng-template #loading>Loading comps...</ng-template>
           \`
         })
         export class MyComponent {}