Rego v1 capabilities and keywords update (#7216)

* Separating v0- and v1 keywords
* Adding `rego_v1` capability feature

Signed-off-by: Johan Fylling <johan.dev@fylling.se>

capabilities.json

@@ -4819,12 +4819,6 @@
       }
     }
   ],
-  "future_keywords": [
-    "contains",
-    "every",
-    "if",
-    "in"
-  ],
   "wasm_abi_versions": [
     {
       "version": 1,
@@ -4836,8 +4830,6 @@
     }
   ],
   "features": [
-    "rule_head_ref_string_prefixes",
-    "rule_head_refs",
-    "rego_v1_import"
+    "rego_v1"
   ]
 }