Update gradle to 6.2.1

[doodla]

I had to modify the Jacoco config to work with the new version of gradle. For some reason, it was crashing with the previous config.

I also updated the Jacoco tool version to the latest ( 0.8.5 )

[codecov-io]

Codecov Report

Merging #640 into master will increase coverage by 0.94%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##             master     #640      +/-   ##
============================================
+ Coverage     76.31%   77.26%   +0.94%     
+ Complexity      610      607       -3     
============================================
  Files            81       81              
  Lines          2297     2296       -1     
  Branches        327      303      -24     
============================================
+ Hits           1753     1774      +21     
- Misses          324      325       +1     
+ Partials        220      197      -23

[doodla]

I have read the CLA Document and I hereby sign the CLA

[pawelpasterz]

Hey @doodla could you change commits message to be more explanatory? Thanks :)

[doodla]

Hey @doodla could you change commits message to be more explanatory? Thanks :)

I responded a similar comment here if anyone else cares.

[bootstraponline]

Thanks for contributing!