test: add notmuch_show_sanitize_all function that is a little more aggressive.

The old notmuch_show_sanitize function only scrubed part of the
filename.  This one scrubs the full filename, as well as the message
id.

test/test-lib.sh

@@ -502,6 +502,12 @@ notmuch_show_sanitize ()
 {
     sed -e "$NOTMUCH_SHOW_FILENAME_SQUELCH"
 }
+notmuch_show_sanitize_all ()
+{
+    sed \
+	-e 's| filename:.*| filename:XXXXX|' \
+	-e 's| id:[^ ]* | id:XXXXX |'
+}
 
 # End of notmuch helper functions