Update dependency ch.qos.logback:logback-classic to v1.5.20

Author: renovate[bot]

build.gradle.kts

@@ -17,7 +17,7 @@ dependencies {
     val ktor_version = "3.3.1"
 
     @Suppress("LocalVariableName")
-    val logback_version = "1.5.19"
+    val logback_version = "1.5.20"
 
     // Ktor server
     implementation("io.ktor:ktor-server-core:$ktor_version")