Bump doxia.version from 1.6 to 1.11.1

Bumps `doxia.version` from 1.6 to 1.11.1.

Updates `org.apache.maven.doxia:doxia-site-renderer` from 1.6 to 1.11.1
- [Release notes](https://github.com/apache/maven-doxia-sitetools/releases)
- [Commits](apache/maven-doxia-sitetools@doxia-sitetools-1.6...doxia-sitetools-1.11.1)

Updates `org.apache.maven.doxia:doxia-core` from 1.6 to 1.11.1
- [Release notes](https://github.com/apache/maven-doxia/releases)
- [Commits](apache/maven-doxia@doxia-1.6...doxia-1.11.1)

---
updated-dependencies:
- dependency-name: org.apache.maven.doxia:doxia-site-renderer
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: org.apache.maven.doxia:doxia-core
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

coherence-spring-site/pom.xml

@@ -26,7 +26,7 @@
 		<coherence.spring.root>${basedir}/..</coherence.spring.root>
 		<helidon.sitegen.version>3.0.5</helidon.sitegen.version>
 		<asciidoctor.diagram.version>2.2.11</asciidoctor.diagram.version>
-		<doxia.version>1.6</doxia.version>
+		<doxia.version>1.11.1</doxia.version>
 
 		<timestamp>${maven.build.timestamp}</timestamp>
 		<maven.build.timestamp.format>yyyy-MM-dd HH:mm</maven.build.timestamp.format>