Bump jira-rest-client.version from 5.2.6 to 6.0.1

Bumps `jira-rest-client.version` from 5.2.6 to 6.0.1.

Updates `com.atlassian.jira:jira-rest-java-client-api` from 5.2.6 to 6.0.1
- [Commits](https://bitbucket.org/atlassian/jira-rest-java-client/branches/compare/jira-rest-java-client-parent-6.0.1..jira-rest-java-client-parent-5.2.6)

Updates `com.atlassian.jira:jira-rest-java-client-core` from 5.2.6 to 6.0.1
- [Commits](https://bitbucket.org/atlassian/jira-rest-java-client/branches/compare/jira-rest-java-client-parent-6.0.1..jira-rest-java-client-parent-5.2.6)

---
updated-dependencies:
- dependency-name: com.atlassian.jira:jira-rest-java-client-api
  dependency-type: direct:production
  update-type: version-update:semver-major
- dependency-name: com.atlassian.jira:jira-rest-java-client-core
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

pom.xml

@@ -13,7 +13,7 @@
   <properties>
     <changelist>999999-SNAPSHOT</changelist>
     <jenkins.version>2.452.3</jenkins.version>
-    <jira-rest-client.version>5.2.7</jira-rest-client.version>
+    <jira-rest-client.version>6.0.1</jira-rest-client.version>
     <fugue.version>4.7.2</fugue.version>
     <gitHubRepo>jenkinsci/${project.artifactId}-plugin</gitHubRepo>
     <spotbugs.threshold>High</spotbugs.threshold>