Bump ch.qos.logback:logback-classic from 1.5.13 to 1.5.15

Bumps [ch.qos.logback:logback-classic](https://github.com/qos-ch/logback) from 1.5.13 to 1.5.15.
- [Commits](qos-ch/logback@v_1.5.13...v_1.5.15)

---
updated-dependencies:
- dependency-name: ch.qos.logback:logback-classic
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

build.gradle.kts

@@ -7,7 +7,7 @@ version = "1.0-SNAPSHOT"
 val coroutinesVersion = "1.8.1"
 val kotlinSerializationVersion = "0.20.0"
 val ktorVersion = "2.3.2"
-val logbackVersion = "1.5.13"
+val logbackVersion = "1.5.15"
 val logstashEncoderVersion = "7.4"
 val prometheusVersion = "0.16.0"
 val jacksonVersion = "2.18.2"