Fixed typo of function name supressMessages() (#285)

Should be suppressMessages()

pipes.Rmd

@@ -185,7 +185,7 @@ This means that the pipe won't work for two classes of functions:
     ```
     
     There are a relatively wide class of functions with this behaviour,
-    including `try()`, `supressMessages()`, and `suppressWarnings()`
+    including `try()`, `suppressMessages()`, and `suppressWarnings()`
     in base R.
   
 ## When not to use the pipe