Improve google event update logic and add logging

src/test/java/de/jeyp91/googlecalendar/TippligaGoogleEventManagerTest.java

@@ -6,6 +6,7 @@ import de.jeyp91.tippliga.TLWMatchday;
 import de.jeyp91.tippliga.TLWMatchdaysCreator;
 import org.junit.Test;
 
+import java.io.IOException;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -94,4 +95,9 @@ public class TippligaGoogleEventManagerTest {
             TippligaGoogleEventManager.deleteEvent(tlwMatchday, 3);
         });
     }
+
+    @Test
+    public void deleteAllEventsTest() throws IOException {
+        TippligaGoogleEventManager.deleteAllEvents(2023);
+    }
 }