repro: Fix chroot version file

Signed-off-by: Morten Linderud <morten@linderud.pw>

Author: Foxboron

repro.in

@@ -232,7 +232,7 @@ function init_chroot(){
         touch "$BUILDDIRECTORY/root/.repro-1"
         lock_close 9
     else
-      if [ ! -d "$BUILDDIRECTORY/root/.repro-1" ]; then
+      if [ ! -f "$BUILDDIRECTORY/root/.repro-1" ]; then
         error "Please delete $BUILDDIRECTORY and initialize the chroots again"
         exit 1
       fi