anagram: words are not anagrams of themselves

The logical extension of Banana not being an anagram of BANANA must be
that words are never anagrams of themselves, and that the test "capital
word is not own anagram" only tests this for case insensitivity.

Author: sshine

exercises/anagram/canonical-data.json

@@ -1,6 +1,6 @@
 {
   "exercise": "anagram",
-  "version": "1.3.0",
+  "version": "1.4.0",
   "cases": [
     {
       "description": "no matches",
@@ -109,11 +109,11 @@
       "expected": []
     },
     {
-      "description": "capital word is not own anagram",
+      "description": "words are not anagrams of themselves (case-insensitive)",
       "property": "findAnagrams",
       "input": {
         "subject": "BANANA",
-        "candidates": ["Banana"]
+        "candidates": ["BANANA", "Banana", "banana"]
       },
       "expected": []
     }