[java-atk-wrapper] Only enable -Werror in upstream development

[Samuel Thibault <sthibaul src gnome org>]

commit 0d4f7ff12356d62b6bd26f0b19ae34beaab9266b
Author: Samuel Thibault <samuel thibault ens-lyon org>
Date:   Wed Mar 3 20:46:21 2021 +0100

    Only enable -Werror in upstream development

 configure.ac | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/configure.ac b/configure.ac
index 995d629..75baacd 100644
--- a/configure.ac
+++ b/configure.ac
@@ -123,6 +123,7 @@ else
 fi
 AC_SUBST(JAW_CFLAGS)
 
+AX_IS_RELEASE(dash-version)
 AX_COMPILER_FLAGS()
 case "$WARN_CFLAGS" in
     *-Werror*)