Update logback-classic to 1.5.15

Author: scala-steward

examples/src/main/scala/sttp/client4/examples/LogRequestsSlf4j.scala

@@ -3,7 +3,7 @@
 //> using dep com.softwaremill.sttp.client4::circe:4.0.0-M20
 //> using dep com.softwaremill.sttp.client4::slf4j-backend:4.0.0-M20
 //> using dep io.circe::circe-generic:0.14.10
-//> using dep ch.qos.logback:logback-classic:1.5.13
+//> using dep ch.qos.logback:logback-classic:1.5.15
 
 package sttp.client4.examples