Update exact query prefix tests

Author: sampsyo

test/test_query.py

@@ -150,7 +150,7 @@ def test_get_one_keyed_exact(self):
         self.assert_items_matched(results, ['beets 4 eva'])
 
     def test_get_one_keyed_exact_nocase(self):
-        q = 'genre:~"hard rock"'
+        q = 'genre:=~"hard rock"'
         results = self.lib.items(q)
         self.assert_items_matched(results, ['beets 4 eva'])
 
@@ -220,7 +220,7 @@ def test_key_case_insensitive(self):
         self.assert_items_matched(results, ['beets 4 eva'])
 
     def test_keyed_matches_exact_nocase(self):
-        q = 'genre:~rock'
+        q = 'genre:=~rock'
         results = self.lib.items(q)
         self.assert_items_matched(results, [
             'foo bar',