snap: build without wrappers

Wrappers usually define things required for snaps to work like library path.
Ripgrep being static binary doesn't need it at all.

This will give minor speed up in scenarios when ripgrep is ran multiple
times and can be considered as good practice for static binaries.

PR #979

snapcraft.yaml

@@ -11,4 +11,5 @@ parts:
     source: .
 apps:
   rg:
-    command: env PATH=$SNAP/bin:$PATH rg
+    adapter: none
+    command: ./bin/rg