Bump net.logstash.logback:logstash-logback-encoder from 8.0 to 8.1

Bumps [net.logstash.logback:logstash-logback-encoder](https://github.com/logfellow/logstash-logback-encoder) from 8.0 to 8.1.
- [Release notes](https://github.com/logfellow/logstash-logback-encoder/releases)
- [Commits](logfellow/logstash-logback-encoder@logstash-logback-encoder-8.0...logstash-logback-encoder-8.1)

---
updated-dependencies:
- dependency-name: net.logstash.logback:logstash-logback-encoder
  dependency-version: '8.1'
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

build.gradle.kts

@@ -10,7 +10,7 @@ val kotlin_version = "2.0.21"
 val kotlinx_datetime_version = "0.6.2"
 val kompendium_version = "4.0.3"
 val logback_version = "1.5.18"
-val logstash_version = "8.0"
+val logstash_version = "8.1"
 val prometeus_version = "1.14.5"
 val nav_common_version = "3.2025.03.25_13.00-69496eec5820"
 val tjenestespec_version = "1.2021.02.22-10.45-4201aaea72fb"