Buffer.slice: Added description for the case when end is greater than…

… buffer length

Fixes nodejs#14714 - issue

doc/api/buffer.md

@@ -1907,6 +1907,9 @@ changes:
 Returns a new `Buffer` that references the same memory as the original, but
 offset and cropped by the `start` and `end` indices.
 
+Specifying 'end' greater than ['buf.length'] will return the same result as that of
+'end' equal to [buf.length]
+
 *Note*: Modifying the new `Buffer` slice will modify the memory in the
 original `Buffer` because the allocated memory of the two objects overlap.