This commit fixes a minor verb conjugation error in gmock_cook_book.md.

PiperOrigin-RevId: 490601453
Change-Id: I733b2ed8740b1c809dddb166a42993b869198469

docs/gmock_cook_book.md

@@ -1904,7 +1904,7 @@ using testing::ReturnPointee;
 ### Combining Actions
 
 Want to do more than one thing when a function is called? That's fine. `DoAll()`
-allow you to do sequence of actions every time. Only the return value of the
+allows you to do a sequence of actions every time. Only the return value of the
 last action in the sequence will be used.
 
 ```cpp