build: move the demos to springdoc 3.1.1

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

Author: bnasslahsen

pom.xml

@@ -101,7 +101,7 @@
 		<maven.compiler.target>${java.version}</maven.compiler.target>
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
 		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
-		<springdoc.version>3.1.1-SNAPSHOT</springdoc.version>
+		<springdoc.version>3.1.1</springdoc.version>
 		<maven-source-plugin.version>3.0.1</maven-source-plugin.version>
 		<maven-javadoc-plugin.version>3.0.1</maven-javadoc-plugin.version>
 		<maven-gpg-plugin.version>1.6</maven-gpg-plugin.version>