Update versions in pom.xml and documentation after 0.4.2 release

[github-actions]

• Versions are updated in pom.xml, README.md and in examples
• Current project version is incremented to the next snapshot

[codecov]

Codecov Report

Merging #794 (a3cffef) into master (5f3ee0e) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master     #794   +/-   ##
=========================================
  Coverage     80.91%   80.91%           
  Complexity     2204     2204           
=========================================
  Files            98       98           
  Lines          5670     5670           
  Branches       1756     1756           
=========================================
  Hits           4588     4588           
  Misses          285      285           
  Partials        797      797           

Flag	Coverage Δ	Complexity Δ
unittests	80.91% <ø> (ø)	0.00 <ø> (ø)

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