[SPARK-32723][WEBUI] Upgrade to jQuery 3.5.1

### What changes were proposed in this pull request?
Upgrade to the latest available version of jQuery (3.5.1).

### Why are the changes needed?
There are some CVE-s reported (CVE-2020-11022, CVE-2020-11023) affecting older versions of jQuery. Although Spark UI is read-only and those CVEs doesn't seem to affect Spark, using the latest version of this library can help to handle vulnerability reports of security scans.

### Does this PR introduce _any_ user-facing change?
No.

### How was this patch tested?
Manual tests and checked the jQuery 3.5 upgrade guide.

Closes apache#29902 from peter-toth/SPARK-32723-upgrade-to-jquery-3.5.1.

Authored-by: Peter Toth <peter.toth@gmail.com>
Signed-off-by: Dongjoon Hyun <dhyun@apple.com>

core/src/main/scala/org/apache/spark/ui/UIUtils.scala

@@ -231,7 +231,7 @@ private[spark] object UIUtils extends Logging {
     <link rel="stylesheet"
           href={prependBaseUri(request, "/static/timeline-view.css")} type="text/css"/>
     <script src={prependBaseUri(request, "/static/sorttable.js")} ></script>
-    <script src={prependBaseUri(request, "/static/jquery-3.4.1.min.js")}></script>
+    <script src={prependBaseUri(request, "/static/jquery-3.5.1.min.js")}></script>
     <script src={prependBaseUri(request, "/static/vis-timeline-graph2d.min.js")}></script>
     <script src={prependBaseUri(request, "/static/bootstrap.bundle.min.js")}></script>
     <script src={prependBaseUri(request, "/static/initialize-tooltips.js")}></script>

dev/.rat-excludes

@@ -25,7 +25,7 @@ bootstrap.bundle.min.js
 bootstrap.bundle.min.js.map
 bootstrap.min.css
 bootstrap.min.css.map
-jquery-3.4.1.min.js
+jquery-3.5.1.min.js
 d3.min.js
 dagre-d3.min.js
 graphlib-dot.min.js

docs/_layouts/global.html

@@ -168,7 +168,7 @@ <h1 class="title">{{ page.title }}</h1>
              <!-- /container -->
         </div>
 
-        <script src="js/vendor/jquery-3.4.1.min.js"></script>
+        <script src="js/vendor/jquery-3.5.1.min.js"></script>
         <script src="js/vendor/bootstrap.bundle.min.js"></script>
         <script src="js/vendor/anchor.min.js"></script>
         <script src="js/main.js"></script>