Add tests to ensure correct order

Author: zbraniecki

tests/fixtures/negotiate/filtering/available-as-range.json

@@ -1,4 +1,24 @@
 [
+  {
+    "input": [["en-US"], ["en"]],
+    "output": ["en"]
+  },
+  {
+    "input": [["en-Latn-US"], ["en-US"]],
+    "output": ["en-US"]
+  },
+  {
+    "input": [["en-US-windows"], ["en-US"]],
+    "output": ["en-US"]
+  },
+  {
+    "input": [["fr-CA", "de-DE"], ["fr", "it", "de"]],
+    "output": ["fr", "de"]
+  },
+  {
+    "input": [["ja-JP-windows"], ["ja"]],
+    "output": ["ja"]
+  },
   {
     "input": [["en-Latn-GB", "en-Latn-IN"], ["en-IN", "en-GB"]],
     "output": ["en-GB", "en-IN"]

tests/fixtures/negotiate/filtering/likely-subtag.json

@@ -34,5 +34,9 @@
   {
     "input": [["sr-RU"], ["sr-Latn-RO", "sr-Cyrl"]],
     "output": ["sr-Latn-RO"]
+  },
+  {
+    "input": [["en-CA"], ["en-ZA", "en-GB", "en-US"]],
+    "output": ["en-US", "en-ZA", "en-GB"]
   }
 ]