Add Javadoc for the newly added uploadFile method.

Signed-off-by: Robin Verduijn <robinverduijn.github@gmail.com>

Author: robinverduijn

src/main/java/io/jenkins/plugins/httpclient/RobustHTTPClient.java

@@ -242,6 +242,12 @@ public void uploadFile(File f, URL url, TaskListener listener) throws IOExceptio
         uploadFile(f, null, url, listener);
     }
 
+    /**
+     * Upload a file to a URL with a specific content type.
+     *
+     * @param f the file to upload
+     * @param contentType the content type for the specified file
+     */
     public void uploadFile(File f, String contentType, URL url, TaskListener listener) throws IOException, InterruptedException {
         connect("upload", "upload " + f + " to " + sanitize(url), client -> {
             HttpPut put = new HttpPut(url.toString());