Fix Javadoc warnings due to Java 21 update (+ some other warnings)

The default implicit constructor must also have a doc comment, so I have to make it explicit and either properly restrict the visibility of the constructor, or actually document it.

pandalib-util/src/main/java/fr/pandacube/lib/util/log/DailyLogRotateFileHandler.java

@@ -30,6 +30,11 @@ public class DailyLogRotateFileHandler extends Handler {
 	private String currentFileDate = getCurrentDay();
 	private boolean closed = false;
 
+	/**
+	 * Creates a new {@link DailyLogRotateFileHandler}.
+	 */
+	public DailyLogRotateFileHandler() {}
+
 
 	@Override
 	public synchronized void close() throws SecurityException {

pandalib-util/src/main/java/fr/pandacube/lib/util/log/Log.java

@@ -159,4 +159,6 @@ public final class Log {
 		logger.info(message);
 	}
 
+	private Log() {}
+
 }