Remove elm-safe-int test dependency since there aren't any tests anyway

elm.json

@@ -12,7 +12,6 @@
         "elm/core": "1.0.0 <= v < 2.0.0"
     },
     "test-dependencies": {
-        "elm-explorations/test": "1.2.2 <= v < 2.0.0",
-        "malaire/elm-safe-int": "1.0.0 <= v < 2.0.0"
+        "elm-explorations/test": "1.2.2 <= v < 2.0.0"
     }
 }