IGNITE-15873 Fixed jetty-server configuration files. Fixes #9558

(cherry picked from commit dc25b35)

Author: sk0x50

docs/_docs/code-snippets/xml/jetty.xml

@@ -17,7 +17,7 @@
 -->
 <!DOCTYPE Configure PUBLIC "-//Jetty//Configure//EN" "http://www.eclipse.org/jetty/configure.dtd">
 <Configure id="Server" class="org.eclipse.jetty.server.Server">
-    <Arg name="threadPool">
+    <Arg name="threadpool">
         <!-- Default queued blocking thread pool -->
         <New class="org.eclipse.jetty.util.thread.QueuedThreadPool">
             <Set name="minThreads">20</Set>

modules/clients/src/test/resources/jetty/rest-jetty-ssl-client-auth.xml

@@ -19,7 +19,7 @@
 
 <!DOCTYPE Configure PUBLIC "-//Jetty//Configure//EN" "http://www.eclipse.org/jetty/configure.dtd">
 <Configure id="Server" class="org.eclipse.jetty.server.Server">
-    <Arg name="threadPool">
+    <Arg name="threadpool">
         <New class="org.eclipse.jetty.util.thread.QueuedThreadPool">
             <Set name="minThreads">5</Set>
             <Set name="maxThreads">10</Set>

modules/clients/src/test/resources/jetty/rest-jetty-ssl.xml

@@ -20,7 +20,7 @@
 <!DOCTYPE Configure PUBLIC "-//Jetty//Configure//EN" "http://www.eclipse.org/jetty/configure.dtd">
 
 <Configure id="Server" class="org.eclipse.jetty.server.Server">
-    <Arg name="threadPool">
+    <Arg name="threadpool">
         <!-- Default queued blocking thread pool -->
         <New class="org.eclipse.jetty.util.thread.QueuedThreadPool">
             <Set name="minThreads">10</Set>

modules/clients/src/test/resources/jetty/router-jetty-ssl.xml

@@ -20,7 +20,7 @@
 <!DOCTYPE Configure PUBLIC "-//Jetty//Configure//EN" "http://www.eclipse.org/jetty/configure.dtd">
 
 <Configure id="Server" class="org.eclipse.jetty.server.Server">
-    <Arg name="threadPool">
+    <Arg name="threadpool">
         <!-- Default queued blocking thread pool -->
         <New class="org.eclipse.jetty.util.thread.QueuedThreadPool">
             <Set name="minThreads">10</Set>

modules/clients/src/test/resources/jetty/router-jetty.xml

@@ -20,7 +20,7 @@
 <!DOCTYPE Configure PUBLIC "-//Jetty//Configure//EN" "http://www.eclipse.org/jetty/configure.dtd">
 
 <Configure id="Server" class="org.eclipse.jetty.server.Server">
-    <Arg name="threadPool">
+    <Arg name="threadpool">
         <!-- Default queued blocking thread pool -->
         <New class="org.eclipse.jetty.util.thread.QueuedThreadPool">
             <Set name="minThreads">20</Set>