[JENKINS-73944] Extract inline event handler from POSTHyperlinkNote (jenkinsci#284)

Author: yaroslavafenkin

src/main/java/org/jenkinsci/plugins/workflow/support/steps/input/POSTHyperlinkNote.java

@@ -83,7 +83,7 @@ public POSTHyperlinkNote(String url, int length) {
 
     @Override protected String extraAttributes() {
         // TODO perhaps add hoverNotification
-        return " onclick=\"fetch(decodeURIComponent(atob('" + encodeForJavascript(url) + "')), { method: 'post', headers: crumb.wrap({})}); return false\"";
+        return " data-encoded-url='" + encodeForJavascript(url) + "' class='post-hyperlink-note-button'";
     }
 
     /**

src/main/resources/org/jenkinsci/plugins/workflow/support/steps/input/POSTHyperlinkNote/script.js

@@ -0,0 +1,10 @@
+Behaviour.specify("A.post-hyperlink-note-button", "POSTHyperLinkNote", 0, function (element) {
+    element.addEventListener("click", (event) => {
+        event.preventDefault();
+        const url = decodeURIComponent(atob(element.dataset.encodedUrl));
+        fetch(url, {
+            method: "post",
+            headers: crumb.wrap({}),
+        });
+    });
+});