ref-manual: Fixed spelling error "containe"

(From yocto-docs rev: cf8032bf7c3bc484b63ee46c195ee1537b1f817f)

Signed-off-by: Kristi Rifenbark <kristi.rifenbark@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

documentation/ref-manual/ref-images.xml

@@ -31,7 +31,7 @@
         From within the <filename>poky</filename> Git repository, you can use
         the following command to display the list of directories within the
         <ulink url='&YOCTO_DOCS_DEV_URL;#source-directory'>Source Directory</ulink>
-        that containe image recipe files:
+        that contain image recipe files:
         <literallayout class='monospaced'>
      $ ls meta*/recipes*/images/*.bb
         </literallayout>