lastgenre: Fix up ragga jungle.

* Move `ragga jungle` to beneath `oldschool jungle`.
* Remove `ragga-jungle` which isn't recognised by the genre whitelist.

https://en.wikipedia.org/wiki/Ragga_jungle

beetsplug/lastgenre/genres-tree.yaml

@@ -291,7 +291,7 @@
         - neurofunk
         - oldschool jungle:
             - darkside jungle
-            - ragga-jungle
+            - ragga jungle
         - raggacore
         - sambass
         - techstep
@@ -740,7 +740,6 @@
     - dancehall
     - dub
     - lovers rock
-    - ragga jungle
-        - polish reggae
+    - polish reggae
     - reggae fusion
     - rocksteady