[shotwell] Add translator comment to new email portal code

[Jens Georg <jensgeorg src gnome org>]

commit 2bbb04c53403ca9f9622f777d2e885bac10a9ea8
Author: Jens Georg <mail jensge org>
Date:   Sun May 29 18:33:20 2022 +0200

    Add translator comment to new email portal code
    
    Fixes #4977

 src/DesktopIntegration.vala | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/src/DesktopIntegration.vala b/src/DesktopIntegration.vala
index 024bc8b2..43a7a93b 100644
--- a/src/DesktopIntegration.vala
+++ b/src/DesktopIntegration.vala
@@ -133,6 +133,7 @@ public async void files_send_to(File[] files) {
             throw new DBusError.FAILED("Did not get response");
         }
     } catch (Error e){
+        // Translators: The first %s is the name of the file, the second %s is the reason why it could not 
be sent
         AppWindow.error_message(_("Unable to send file %s, %s").printf(
         file_names.str, e.message));
     }