Update to jQuery 3.6.0

This covers the following GitHub security advisories:
- GHSA-gxr4-xjj5-5px2
- GHSA-jpcq-cgw6-v4j6
- CVE-2019-11358
- CVE-2015-9251

The jQuery Migrate library is also added to maintain compatibility
with the current Bootstrap version (2.0.4). Without the compatibility
library, the following error occurs when dismissing an alert:

  Uncaught Error: Syntax error, unrecognized expression: #
      jQuery (7)
      close http://localhost:8888/static/js/bootstrap.js:7
      jQuery (8)
      <anonymous> http://localhost:8888/static/js/bootstrap.js:7
      jQuery (13)
  jquery-3.6.0.min.js:2:13639

Author: andreyv

cms/server/admin/templates/base.html

@@ -7,7 +7,7 @@
     <link rel="stylesheet" type="text/css" href="{{ url("static", "aws_style.css") }}">
     <script src="{{ url("static", "web_rpc.js") }}"></script>
     <script src="{{ url("static", "aws_utils.js") }}"></script>
-    <script src="{{ url("static", "jq", "jquery-1.12.4.min.js") }}"></script>
+    <script src="{{ url("static", "jq", "jquery-3.6.0.min.js") }}"></script>
     <script src="{{ url("static", "jq", "jquery.jqplot.min.js") }}"></script>
     <script src="{{ url("static", "jq", "jqplot.dateAxisRenderer.min.js") }}"></script>
     <script src="{{ url("static", "jq", "jqplot.enhancedLegendRenderer.min.js") }}"></script>

cms/server/contest/templates/base.html

@@ -10,7 +10,9 @@
         <link rel="stylesheet" href="{{ url("static", "css", "bootstrap.css") }}">
         <link rel="stylesheet" href="{{ url("static", "cws_style.css") }}">
 
-        <script src="{{ url("static", "jq", "jquery-1.12.4.min.js") }}"></script>
+        <script src="{{ url("static", "jq", "jquery-3.6.0.min.js") }}"></script>
+        {# For compatibility with Bootstrap 2.x #}
+        <script src="{{ url("static", "jq", "jquery-migrate-3.3.2.min.js") }}"></script>
         <script src="{{ url("static", "js", "bootstrap.js") }}"></script>
         <script src="{{ url("static", "cws_utils.js") }}"></script>
 

cms/server/static/jq/jquery-1.12.4.min.js

@@ -4,7 +4,7 @@
         <meta charset='utf-8'/>
         <link rel="shortcut icon" href="img/favicon.ico" />
         <link rel='stylesheet' href='Ranking.css'>
-        <script src="//ajax.googleapis.com/ajax/libs/jquery/1.12.4/jquery.min.js"></script>
+        <script src="//ajax.googleapis.com/ajax/libs/jquery/3.6.0/jquery.min.js"></script>
         <script>
 if (typeof jQuery == 'undefined') {
     document.write(unescape("%3Cscript src='lib/jquery.js'%3E%3C/script%3E"));

cms/server/static/jq/jquery-3.6.0.min.js

@@ -15,7 +15,7 @@ Copyright: 2011-2012 Luca Wehrstedt <luca.wehrstedt@gmail.com>
 License: CC-BY-SA-3.0
 
 Files: cmsranking/static/lib/jquery.js
-Copyright: 2016 jQuery Foundation and other contributors, http://jquery.org/
+Copyright: 2021 OpenJS Foundation and other contributors, http://jquery.org/
 License: Expat
 Comment: See http://jquery.org/license
 
@@ -35,8 +35,9 @@ Copyright: 2008-2016 Dmitry Baranovskiy (http://raphaeljs.com)
 License: Expat and Apache-2.0
 Comment: See https://dmitrybaranovskiy.github.io/raphael/license.html
 
-Files: cms/server/static/jq/jquery-1.12.4.min.js
-Copyright: 2016 jQuery Foundation and other contributors, http://jquery.org/
+Files: cms/server/static/jq/jquery-3.6.0.min.js
+       cms/server/static/jq/jquery-migrate-3.3.2.min.js
+Copyright: 2021 OpenJS Foundation and other contributors, http://jquery.org/
 License: Expat
 
 Files: cms/server/static/jq/jquery.jqplot*