Bump doxia-sitetoolsVersion from 1.11.1 to 2.0.0

Bumps `doxia-sitetoolsVersion` from 1.11.1 to 2.0.0.

Updates `org.apache.maven.doxia:doxia-site-renderer` from 1.11.1 to 2.0.0
- [Release notes](https://github.com/apache/maven-doxia-sitetools/releases)
- [Commits](apache/maven-doxia-sitetools@doxia-sitetools-1.11.1...doxia-sitetools-2.0.0)

Updates `org.apache.maven.doxia:doxia-integration-tools` from 1.11.1 to 2.0.0
- [Release notes](https://github.com/apache/maven-doxia-sitetools/releases)
- [Commits](apache/maven-doxia-sitetools@doxia-sitetools-1.11.1...doxia-sitetools-2.0.0)

Updates `org.apache.maven.doxia:doxia-module-xhtml5` from 1.11.1 to 2.0.0

---
updated-dependencies:
- dependency-name: org.apache.maven.doxia:doxia-site-renderer
  dependency-type: direct:production
  update-type: version-update:semver-major
- dependency-name: org.apache.maven.doxia:doxia-integration-tools
  dependency-type: direct:development
  update-type: version-update:semver-major
- dependency-name: org.apache.maven.doxia:doxia-module-xhtml5
  dependency-type: direct:development
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

pom.xml

@@ -121,7 +121,7 @@
   <properties>
     <mavenVersion>3.6.3</mavenVersion>
     <doxiaVersion>1.12.0</doxiaVersion>
-    <doxia-sitetoolsVersion>1.11.1</doxia-sitetoolsVersion>
+    <doxia-sitetoolsVersion>2.0.0</doxia-sitetoolsVersion>
     <mockitoVersion>4.11.0</mockitoVersion>
     <pluginVersion>${project.version}</pluginVersion>
     <sitePluginVersion>${maven-site-plugin.version}</sitePluginVersion>