Update vulnerable checkstyle dependency

[wandi34]

Summary

Update a mvn dependency, which is vulnerable.

mvn dependency

<groupId>com.puppycrawl.tools</groupId>
            <artifactId>checkstyle</artifactId>

has a security issue in versions below 8.18.

Checklist for Definition of Done

Depending on the task some of the following jobs are not relevant. Please check the items or cross them out (~~text~~).

• [x] Code is technically reviewed by myself
• [x] Code is manually tested
• [x] Automatic tests for new functionality are created
• [x] Documentation is updated
• [x] Git history is clean

[codecov[bot]]

Codecov Report

Merging #94 into master will not change coverage. The diff coverage is n/a.

@@            Coverage Diff            @@
##             master      #94   +/-   ##
=========================================
  Coverage     71.55%   71.55%           
  Complexity      290      290           
=========================================
  Files            77       77           
  Lines          1610     1610           
  Branches        112      112           
=========================================
  Hits           1152     1152           
  Misses          396      396           
  Partials         62       62

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