docs: mention entryComponents is no longer necessary

https://angular.io/guide/deprecations#entrycomponents-and-analyze_for_entry_components-no-longer-required

Author: AlexElin

src/material/bottom-sheet/bottom-sheet.md

@@ -50,6 +50,8 @@ export class HobbitSheet {
 ```
 
 ### Configuring bottom sheet content via `entryComponents`
+**This is only necessary if your project is using ViewEngine. It doesn't have to be specified for 
+projects running on Ivy.**
 
 Similarly to `MatDialog`, `MatBottomSheet` instantiates components at run-time. In order for it to
 work, the Angular compiler needs extra information to create the necessary `ComponentFactory` for

src/material/dialog/dialog.md

@@ -40,6 +40,8 @@ export class YourDialog {
 ```
 
 ### Configuring dialog content via `entryComponents`
+**This is only necessary if your project is using ViewEngine. It doesn't have to be specified for
+projects running on Ivy.**
 
 Because `MatDialog` instantiates components at run-time, the Angular compiler needs extra
 information to create the necessary `ComponentFactory` for your dialog content component.