Site plugin fails if there's a & in the project <url> POM

  <url>http://extensions.xwiki.org?id=${project.groupId}:${project.artifactId}&amp;path=</url>

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-site-plugin:3.0:site (default-site) on project xwiki-commons: SiteToolException: Error parsing site descriptor: entity reference name can not contain character =' (position: TEXT seen ...tp://extensions.xwiki.org?id=org.xwiki.commons:xwiki-commons&path=... @27:121) -> [Help 1]
org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal org.apache.maven.plugins:maven-site-plugin:3.0:site (default-site) on project xwiki-commons: SiteToolException: Error parsing site descriptor
	at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:217)
	at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:153)
	at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:145)
	at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:84)
	at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:59)
	at org.apache.maven.lifecycle.internal.LifecycleStarter.singleThreadedBuild(LifecycleStarter.java:183)
	at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:161)
	at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:319)
	at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:156)
	at org.apache.maven.cli.MavenCli.execute(MavenCli.java:537)
	at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:196)
	at org.apache.maven.cli.MavenCli.main(MavenCli.java:141)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:597)
	at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:290)
	at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:230)
	at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:409)
	at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:352)
Caused by: org.apache.maven.plugin.MojoExecutionException: SiteToolException: Error parsing site descriptor
	at org.apache.maven.plugins.site.AbstractSiteRenderingMojo.createSiteRenderingContext(AbstractSiteRenderingMojo.java:293)
	at org.apache.maven.plugins.site.SiteMojo.renderLocale(SiteMojo.java:154)
	at org.apache.maven.plugins.site.SiteMojo.execute(SiteMojo.java:138)
	at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:101)
	at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:209)
	... 19 more
Caused by: org.apache.maven.doxia.tools.SiteToolException: Error parsing site descriptor
	at org.apache.maven.doxia.tools.DefaultSiteTool.readDecorationModel(DefaultSiteTool.java:1249)
	at org.apache.maven.doxia.tools.DefaultSiteTool.getDecorationModel(DefaultSiteTool.java:480)
	at org.apache.maven.plugins.site.AbstractSiteRenderingMojo.createSiteRenderingContext(AbstractSiteRenderingMojo.java:286)
	... 23 more
Caused by: org.codehaus.plexus.util.xml.pull.XmlPullParserException: entity reference name can not contain character =' (position: TEXT seen ...tp://extensions.xwiki.org?id=org.xwiki.commons:xwiki-commons&path=... @27:121) 
	at org.codehaus.plexus.util.xml.pull.MXParser.parseEntityRef(MXParser.java:2219)
	at org.codehaus.plexus.util.xml.pull.MXParser.parseAttribute(MXParser.java:2044)
	at org.codehaus.plexus.util.xml.pull.MXParser.parseStartTag(MXParser.java:1796)
	at org.codehaus.plexus.util.xml.pull.MXParser.nextImpl(MXParser.java:1127)
	at org.codehaus.plexus.util.xml.pull.MXParser.next(MXParser.java:1093)
	at org.codehaus.plexus.util.xml.pull.MXParser.nextTag(MXParser.java:1080)
	at org.apache.maven.doxia.site.decoration.io.xpp3.DecorationXpp3Reader.parseBody(DecorationXpp3Reader.java:893)
	at org.apache.maven.doxia.site.decoration.io.xpp3.DecorationXpp3Reader.parseDecorationModel(DecorationXpp3Reader.java:1024)
	at org.apache.maven.doxia.site.decoration.io.xpp3.DecorationXpp3Reader.read(DecorationXpp3Reader.java:1588)
	at org.apache.maven.doxia.site.decoration.io.xpp3.DecorationXpp3Reader.read(DecorationXpp3Reader.java:1521)
	at org.apache.maven.doxia.site.decoration.io.xpp3.DecorationXpp3Reader.read(DecorationXpp3Reader.java:1535)
	at org.apache.maven.doxia.tools.DefaultSiteTool.readDecorationModel(DefaultSiteTool.java:1245)
	... 25 more