chore: fix detach typos in overlay and portal (#1840)

src/lib/core/overlay/overlay-ref.ts

@@ -33,12 +33,12 @@ export class OverlayRef implements PortalHost {
   }
 
   detach(): Promise<any> {
-    this._detatchBackdrop();
+    this._detachBackdrop();
     return this._portalHost.detach();
   }
 
   dispose(): void {
-    this._detatchBackdrop();
+    this._detachBackdrop();
     this._portalHost.dispose();
   }
 
@@ -101,7 +101,7 @@ export class OverlayRef implements PortalHost {
   }
 
   /** Detaches the backdrop (if any) associated with the overlay. */
-  private _detatchBackdrop(): void {
+  private _detachBackdrop(): void {
     let backdropToDetach = this._backdropElement;
 
     if (backdropToDetach) {

src/lib/core/portal/portal-directives.ts

@@ -97,7 +97,7 @@ export class PortalHostDirective extends BasePortalHost implements OnDestroy {
     return new Map<string, any>();
   }
 
-  /** Detatches the currently attached Portal (if there is one) and attaches the given Portal. */
+  /** Detaches the currently attached Portal (if there is one) and attaches the given Portal. */
   private _replaceAttachedPortal(p: Portal<any>): void {
     if (this.hasAttached()) {
       this.detach();

src/lib/core/portal/portal.ts

@@ -56,7 +56,7 @@ export abstract class Portal<T> {
 
   /**
    * Sets the PortalHost reference without performing `attach()`. This is used directly by
-   * the PortalHost when it is performing an `attach()` or `detatch()`.
+   * the PortalHost when it is performing an `attach()` or `detach()`.
    */
   setAttachedHost(host: PortalHost) {
     this._attachedHost = host;