chore: do not override config file when installing deb package

.goreleaser.yml

@@ -83,7 +83,7 @@ nfpms:
         dst: /etc/systemd/system/glider@.service
 
       - src: config/glider.conf.example
-        dst: /etc/glider/glider.conf
+        dst: /etc/glider/glider.conf.example
 
     scripts:
       postinstall: "systemd/postinstall.sh"

systemd/postinstall.sh

@@ -2,6 +2,10 @@
 
 set -e
 
+if test ! -f "/etc/glider/glider.conf"; then
+    cp /etc/glider/glider.conf.example /etc/glider/glider.conf
+fi
+
 /bin/systemctl daemon-reload
 
 if /bin/systemctl is-active --quiet glider@glider; then
@@ -10,4 +14,4 @@ fi
 
 if ! /bin/systemctl is-enabled --quiet glider@glider; then
     /bin/systemctl enable --now glider@glider;
-fi
+fi