Update PMD to version 6.0.0

[SpOOnman]

No description provided.

[codecov-io]

Codecov Report

Merging #174 into master will decrease coverage by 0.19%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##             master    #174     +/-   ##
==========================================
- Coverage     77.49%   77.3%   -0.2%     
+ Complexity      640     631      -9     
==========================================
  Files           144     144             
  Lines          1964    1943     -21     
  Branches        143     138      -5     
==========================================
- Hits           1522    1502     -20     
+ Misses          381     380      -1     
  Partials         61      61

Impacted Files	Coverage Δ	Complexity Δ
...va/pl/touk/sputnik/processor/pmd/PmdProcessor.java	87.03% <100%> (-2.3%)	9 <1> (-9)

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