chore(deps-dev): bump org.openapitools:openapi-generator-maven-plugin (#314)

Bumps org.openapitools:openapi-generator-maven-plugin from 7.20.0 to 7.21.0.

---
updated-dependencies:
- dependency-name: org.openapitools:openapi-generator-maven-plugin
  dependency-version: 7.21.0
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

pom.xml

@@ -32,7 +32,7 @@
         <maven.jacoco-plugin.version>0.8.14</maven.jacoco-plugin.version>
         <maven.jxr-plugin.version>3.6.0</maven.jxr-plugin.version>
         <maven.license-plugin.version>2.7.1</maven.license-plugin.version>
-        <maven.openapi-generator-plugin.version>7.20.0</maven.openapi-generator-plugin.version>
+        <maven.openapi-generator-plugin.version>7.21.0</maven.openapi-generator-plugin.version>
         <maven.project-info-reports-plugin.version>3.9.0</maven.project-info-reports-plugin.version>
         <maven.rat-plugin.version>0.18</maven.rat-plugin.version>
         <maven.refactor-first-plugin.version>0.8.0</maven.refactor-first-plugin.version>