fix: add log4j xsl from main repo

log4j2-docker.xslt

@@ -0,0 +1,43 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+
+    eXist-db Open Source Native XML Database
+    Copyright (C) 2001 The eXist-db Authors
+
+    [email protected]
+    http://www.exist-db.org
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Lesser General Public
+    License as published by the Free Software Foundation; either
+    version 2.1 of the License, or (at your option) any later version.
+
+    This library is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public
+    License along with this library; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+
+-->
+<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
+    version="2.0">
+
+    <xsl:output method="xml" indent="yes" omit-xml-declaration="no"/>
+
+    <xsl:template match="Root[@level eq 'info']|Logger[@name eq 'org.exist.repo']">
+        <xsl:copy>
+            <xsl:apply-templates select="node()|@*"/>
+            <AppenderRef ref="STDOUT"/>
+        </xsl:copy>
+    </xsl:template>
+
+    <xsl:template match="node()|@*">
+        <xsl:copy>
+            <xsl:apply-templates select="node()|@*"/>
+        </xsl:copy>
+    </xsl:template>
+
+</xsl:stylesheet>