Bump pipeline-model-definition-plugin.version in /bom-latest

Bumps `pipeline-model-definition-plugin.version` from 1.8.3 to 1.8.4.

Updates `pipeline-model-api` from 1.8.3 to 1.8.4
- [Release notes](https://github.com/jenkinsci/pipeline-model-definition-plugin/releases)
- [Changelog](https://github.com/jenkinsci/pipeline-model-definition-plugin/blob/master/CHANGELOG.md)
- [Commits](jenkinsci/pipeline-model-definition-plugin@pipeline-model-definition-1.8.3...pipeline-model-definition-1.8.4)

Updates `pipeline-model-definition` from 1.8.3 to 1.8.4
- [Release notes](https://github.com/jenkinsci/pipeline-model-definition-plugin/releases)
- [Changelog](https://github.com/jenkinsci/pipeline-model-definition-plugin/blob/master/CHANGELOG.md)
- [Commits](jenkinsci/pipeline-model-definition-plugin@pipeline-model-definition-1.8.3...pipeline-model-definition-1.8.4)

Updates `pipeline-model-definition` from 1.8.3 to 1.8.4
- [Release notes](https://github.com/jenkinsci/pipeline-model-definition-plugin/releases)
- [Changelog](https://github.com/jenkinsci/pipeline-model-definition-plugin/blob/master/CHANGELOG.md)
- [Commits](jenkinsci/pipeline-model-definition-plugin@pipeline-model-definition-1.8.3...pipeline-model-definition-1.8.4)

Updates `pipeline-model-extensions` from 1.8.3 to 1.8.4
- [Release notes](https://github.com/jenkinsci/pipeline-model-definition-plugin/releases)
- [Changelog](https://github.com/jenkinsci/pipeline-model-definition-plugin/blob/master/CHANGELOG.md)
- [Commits](jenkinsci/pipeline-model-definition-plugin@pipeline-model-definition-1.8.3...pipeline-model-definition-1.8.4)

Updates `pipeline-stage-tags-metadata` from 1.8.3 to 1.8.4
- [Release notes](https://github.com/jenkinsci/pipeline-model-definition-plugin/releases)
- [Changelog](https://github.com/jenkinsci/pipeline-model-definition-plugin/blob/master/CHANGELOG.md)
- [Commits](jenkinsci/pipeline-model-definition-plugin@pipeline-model-definition-1.8.3...pipeline-model-definition-1.8.4)

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

bom-latest/pom.xml

@@ -12,7 +12,7 @@
         <checks-api.version>1.5.0</checks-api.version>
         <configuration-as-code-plugin.version>1.47</configuration-as-code-plugin.version>
         <git-plugin.version>4.5.2</git-plugin.version>
-        <pipeline-model-definition-plugin.version>1.8.3</pipeline-model-definition-plugin.version>
+        <pipeline-model-definition-plugin.version>1.8.4</pipeline-model-definition-plugin.version>
         <scm-api-plugin.version>2.6.4</scm-api-plugin.version>
         <structs-plugin.version>1.21</structs-plugin.version>
         <workflow-api-plugin.version>2.41</workflow-api-plugin.version>