docs(testing): configureTestModule -> configureTestingModule (#2767)

Author: ppitonak

public/docs/ts/latest/guide/testing.jade

@@ -470,7 +470,7 @@ a(href="#top").to-top Back to top
   `TestBed.createComponent` creates an instance of `BannerComponent` to test and returns a [fixture](#component-fixture).
 
   `TestBed.createComponent` closes the current `TestBed` instance to further configuration.
-  You cannot call any more `TestBed` configuration methods, not `configureTestModule` 
+  You cannot call any more `TestBed` configuration methods, not `configureTestingModule` 
   nor any of the `override...` methods. The `TestBed` throws an error if you try.
 
 .alert.is-important
@@ -874,7 +874,7 @@ a(href="#top").to-top Back to top
 
   ### _compileComponents_ closes configuration
   Calling `compileComponents` closes the current `TestBed` instance is further configuration.
-  You cannot call any more `TestBed` configuration methods, not `configureTestModule` 
+  You cannot call any more `TestBed` configuration methods, not `configureTestingModule` 
   nor any of the `override...` methods. The `TestBed` throws an error if you try.
 
 .alert.is-important
@@ -1114,7 +1114,7 @@ a(href="#top").to-top Back to top
 
 :marked
   The `inject` function closes the current `TestBed` instance to further configuration.
-  You cannot call any more `TestBed` configuration methods, not `configureTestModule`
+  You cannot call any more `TestBed` configuration methods, not `configureTestingModule`
   nor any of the `override...` methods. The `TestBed` throws an error if you try.
 
 .alert.is-important