Adds some tests, cleanup a bit

whisper/base/src/test/java/com/github/gtache/autosubtitle/whisper/base/TestWhisperExtractionModelProvider.java

@@ -10,7 +10,11 @@ import static org.junit.jupiter.api.Assertions.assertEquals;
 
 class TestWhisperExtractionModelProvider {
 
-    private final ExtractionModelProvider provider = new WhisperExtractionModelProvider();
+    private final ExtractionModelProvider provider;
+
+    TestWhisperExtractionModelProvider() {
+        this.provider = new WhisperExtractionModelProvider();
+    }
 
     @Test
     void testGetAvailableExtractionModels() {