fix(server): fix model version in generated POM

Author: Vampire

maven-binding-builder/src/main/kotlin/io/github/typesafegithub/workflows/mavenbinding/PomBuilding.kt

@@ -11,7 +11,7 @@ internal fun buildPomFile(
     return """
         <?xml version="1.0" encoding="UTF-8"?>
         <project xmlns="http://maven.apache.org/POM/4.0.0" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
-          <modelVersion>3.0/0</modelVersion>
+          <modelVersion>4.0.0</modelVersion>
           <groupId>$owner</groupId>
           <artifactId>$name</artifactId>
           <version>$version</version>