Fix DG UML Diagrams and Modify rb9823.md

[RB9823]

Does not work on every version of Java 11

[codecov[bot]]

Codecov Report

Merging #285 (a894e51) into master (210807d) will not change coverage. The diff coverage is n/a.

@@            Coverage Diff            @@
##             master     #285   +/-   ##
=========================================
  Coverage     70.20%   70.20%           
  Complexity      564      564           
=========================================
  Files            93       93           
  Lines          1873     1873           
  Branches        214      214           
=========================================
  Hits           1315     1315           
  Misses          481      481           
  Partials         77       77           

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[markgcera]

LGTM