set git-core paths in snap (#13711)

Signed-off-by: artivis <deray.jeremie@gmail.com>

Co-authored-by: techknowlogick <techknowlogick@gitea.io>

snap/snapcraft.yaml

@@ -19,6 +19,8 @@ architectures:
 environment:
   GITEA_CUSTOM: "$SNAP_COMMON"
   GITEA_WORK_DIR: "$SNAP_DATA"
+  GIT_TEMPLATE_DIR: "$SNAP/usr/share/git-core/templates"
+  GIT_EXEC_PATH: "$SNAP/usr/lib/git-core"
 
 apps:
   gitea: