fix: do not reset GuaranteeE2ee in the database when resending messages

Otherwise if the message is loaded by the UI
after GuaranteeE2ee is reset but before SMTP queue item
is created, the message may appear as unencrypted
even if it was actually resent as encrypted.

src/message.rs

@@ -1366,17 +1366,6 @@ impl Message {
         Ok(())
     }
 
-    pub(crate) async fn update_subject(&self, context: &Context) -> Result<()> {
-        context
-            .sql
-            .execute(
-                "UPDATE msgs SET subject=? WHERE id=?;",
-                (&self.subject, self.id),
-            )
-            .await?;
-        Ok(())
-    }
-
     /// Gets the error status of the message.
     ///
     /// A message can have an associated error status if something went wrong when sending or