bump logback.version from 1.4.14 to 1.5.6

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

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

pom.xml

@@ -29,7 +29,7 @@
     <io7m.api.previousVersion>0.0.1-SNAPSHOT</io7m.api.previousVersion>
     <io7m.java.targetJavaVersion>21</io7m.java.targetJavaVersion>
     <junit.version>5.8.2</junit.version>
-    <logback.version>1.4.14</logback.version>
+    <logback.version>1.5.6</logback.version>
   </properties>
 
   <licenses>