[geary] Fix brown-paper-bag build failure.

[Michael Gratton <mjog src gnome org>]

commit cf6b8ccc6dcf0d8e16efb46b2b9478a50e198bdf
Author: Michael James Gratton <mike vee net>
Date:   Sat Aug 4 15:35:01 2018 +1000

    Fix brown-paper-bag build failure.

 src/engine/rfc822/rfc822-message-data.vala | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/engine/rfc822/rfc822-message-data.vala b/src/engine/rfc822/rfc822-message-data.vala
index f70f0ba4..705bac4c 100644
--- a/src/engine/rfc822/rfc822-message-data.vala
+++ b/src/engine/rfc822/rfc822-message-data.vala
@@ -184,7 +184,7 @@ public class Geary.RFC822.Date : Geary.RFC822.MessageData, Geary.MessageData.Abs
         DateTime? value = new DateTime.from_unix_local(this.as_time_t);
         if (value == null) {
             throw new ImapError.PARSE_ERROR(
-                "Unable to parse \"%s\": Outside supported range", iso8601,
+                "Unable to parse \"%s\": Outside supported range", iso8601
             );
         }
         this.value = value;