Ensure backward compatibility while adding support for configuring the ping interval

- ref. https://github.com/reactor/reactor-netty/actions/runs/13095356929/job/36537031690?pr=3612

Signed-off-by: raccoonback <[email protected]>

Author: raccoonback

reactor-netty-http/src/main/java/reactor/netty/http/Http2SettingsSpec.java

@@ -108,7 +108,9 @@ public interface Builder {
 		 * @return {@code this}
 		 * @since 1.2.3
 		 */
-		Builder pingInterval(Duration pingInterval);
+		default Builder pingInterval(Duration pingInterval) {
+			return this;
+		}
 	}
 
 	/**