fix build script not overwriting app_version

--HG--
branch : nmdc-ircfrontend

typedefs.go

@@ -18,8 +18,11 @@ You should have received a copy of the GNU Affero General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
+var (
+	APP_VERSION = "1.x.x-dev" // overridden with build ldflags
+)
+
 const (
-	APP_VERSION          = "1.x.x-dev" // override with build ldflags
 	APP_NAME             = "nmdc-ircfrontend"
 	BLESSED_CHANNEL      = "#chat" // must be lowercase
 	BLESSED_CHANNEL_MODE = "n"     // means that you have to be in the channel to chat, but that's it