Add test case for classify_audio function

- Implemented test case to verify audio classification with YAMNet
- Used 'cafe_crowd_talk.wav' as test file, expecting 'Speech' as the output class

tests/test_preprocessing.py

@@ -2,6 +2,7 @@ import pytest
 import librosa
 from src.preprocessing.normalize import normalize_audio
 from src.preprocessing.trim import trim_audio
+from src.preprocessing.classify import classify_audio
 from src.input.file_reader import read_audio
 
 def test_normalize_audio():
@@ -17,4 +18,11 @@ def test_trim_audio():
     audio, sr = read_audio(file_path)
     trimmed_audio = trim_audio(audio, sr)
 
-    assert len(trimmed_audio) <= len(audio)
+    assert len(trimmed_audio) <= len(audio)
+
+def test_classify():
+    file_path = "samples/cafe_crowd_talk.wav"
+    expected_class = "Speech"
+    predicted_class = classify_audio(file_path)
+
+    assert predicted_class == expected_class , f"Expected {expected_class}, but got {predicted_class}"