FileUrlResource.isWritable() exclusively relies on getFile() implementation

Closes gh-25584

(cherry picked from commit c6cc670)

Author: jhoeller

spring-core/src/main/java/org/springframework/core/io/FileUrlResource.java

@@ -89,15 +89,8 @@ public File getFile() throws IOException {
 	@Override
 	public boolean isWritable() {
 		try {
-			URL url = getURL();
-			if (ResourceUtils.isFileURL(url)) {
-				// Proceed with file system resolution
-				File file = getFile();
-				return (file.canWrite() && !file.isDirectory());
-			}
-			else {
-				return true;
-			}
+			File file = getFile();
+			return (file.canWrite() && !file.isDirectory());
 		}
 		catch (IOException ex) {
 			return false;