Update kotlin monorepo to v1.9.20

Author: renovate[bot]

pom.xml

@@ -15,7 +15,7 @@
         <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
 
         <java.version>1.8</java.version>
-        <kotlin.version>1.7.0</kotlin.version>
+        <kotlin.version>1.9.20</kotlin.version>
 
         <assertj.version>3.23.1</assertj.version>
         <java-jwt.version>3.19.2</java-jwt.version>