Add test case to validate available languages (#21)

* Add test case to validate available languages

* Fix typo in test case
Resolve variable name warning

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Co-authored-by: Daniel McKnight <daniel@neon.ai>

tests/test_stt.py

@@ -52,6 +52,12 @@ def test_get_stt(self):
                 result = self.stt.execute(audio)
                 self.assertIn(transcription, result)
 
+    def test_available_languages(self):
+        langs = self.stt.available_languages
+        self.assertIsInstance(langs, set)
+        self.assertTrue(all((isinstance(lang, str) for lang in langs)))
+        self.assertIn("en", langs)
+
 
 if __name__ == '__main__':
     unittest.main()