GUACAMOLE-1594: Update all Java and JavaScript dependencies to latest compatible.

NOTE: Several WebPack plugins could not be updated as all plugins within
WebPack's "webpack-contrib" have dropped support for WebPack v4
entirely, but Closure Compiler only supports WebPack v4.

doc/licenses/apache-commons-pool-2.11.1/NOTICE

@@ -0,0 +1,5 @@
+Apache Commons Pool
+Copyright 2001-2021 The Apache Software Foundation
+
+This product includes software developed at
+The Apache Software Foundation (https://www.apache.org/).

doc/licenses/apache-commons-pool-2.11.1/README

@@ -0,0 +1,8 @@
+Apache Commons Pool (http://commons.apache.org/proper/commons-pool/)
+--------------------------------------------------------------------
+
+    Version: 2.11.1
+    From: 'Apache Software Foundation' (https://www.apache.org/)
+    License(s):
+        Apache v2.0
+

doc/licenses/apache-commons-pool-2.11.1/dep-coordinates.txt

@@ -0,0 +1 @@
+org.apache.commons:commons-pool2:jar:2.11.1