Bump logstash-logback-encoder from 7.3 to 7.4 (#698)

Bumps [logstash-logback-encoder](https://github.com/logfellow/logstash-logback-encoder) from 7.3 to 7.4.
- [Release notes](https://github.com/logfellow/logstash-logback-encoder/releases)
- [Commits](logfellow/logstash-logback-encoder@logstash-logback-encoder-7.3...logstash-logback-encoder-7.4)

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

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

pom.xml

@@ -75,7 +75,7 @@
         <logback-access.version>1.3.8</logback-access.version>
         <logback-classic.version>1.3.8</logback-classic.version>
         <logback-core.version>1.3.8</logback-core.version>
-        <logstash.version>7.3</logstash.version>
+        <logstash.version>7.4</logstash.version>
         <mongodb-driver-core.version>4.9.1</mongodb-driver-core.version>
         <mongodb-driver-reactivestreams.version>4.9.1</mongodb-driver-reactivestreams.version>
         <mongodb-driver-sync.version>4.9.1</mongodb-driver-sync.version>