Fix incompatible intersecting types issue

Author: Gamebuster19901

src/main/java/net/fabricmc/loader/impl/game/GameProvider.java

@@ -90,7 +90,7 @@ default boolean hasAwtSupport() {
 		return LoaderUtil.hasAwtSupport();
 	}
 
-	default <T extends ClassLoader & URLLoader> T getProviderCL() {
+	default URLLoader getProviderCL() {
 		return null;
 	}
 

src/main/java/net/fabricmc/loader/impl/launch/knot/KnotClassLoader.java

@@ -53,7 +53,7 @@ public void addURL(URL url) {
 	private final KnotClassDelegate<KnotClassLoader> delegate;
 
 	KnotClassLoader(boolean isDevelopment, EnvType envType, GameProvider provider) {
-		super("knot", provider.getProviderCL() == null ? new DynamicURLClassLoader(new URL[0]) : provider.getProviderCL());
+		super("knot", provider.getProviderCL() == null ? new DynamicURLClassLoader(new URL[0]) : (ClassLoader)provider.getProviderCL());
 		this.originalLoader = getClass().getClassLoader();
 		this.urlLoader = (URLLoader) getParent();
 		this.delegate = new KnotClassDelegate<>(isDevelopment, envType, this, originalLoader, provider);