Bump ch.qos.logback:logback-classic from 1.2.9 to 1.2.13 in /backend

Bumps [ch.qos.logback:logback-classic](https://github.com/qos-ch/logback) from 1.2.9 to 1.2.13.
- [Commits](qos-ch/logback@v_1.2.9...v_1.2.13)

---
updated-dependencies:
- dependency-name: ch.qos.logback:logback-classic
  dependency-type: direct:development
...

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

backend/pom.xml

@@ -26,7 +26,7 @@
     <commons-compress.version>1.21</commons-compress.version>
     <jackson.version>2.13.0</jackson.version>
     <junit.version>5.8.2</junit.version>
-    <logback.version>1.2.9</logback.version>
+    <logback.version>1.2.13</logback.version>
     <mockito.version>4.2.0</mockito.version>
     <slf4j.version>1.7.32</slf4j.version>