Update processJustificationAndFinalization(), per current specs

[farazdagi]

What type of PR is this?

Other / Cleanup

What does this PR do? Why is it needed?

• In the current specs the process_justification_and_finalization() has been updated, most of functions body was extracted into weigh_justification_and_finalization() (see Justification and Finalization)
• This PR does the corresponding update to our code:
  • weighJustificationAndFinalization() function is introduced
  • ProcessJustificationAndFinalizationPreCompute() calls that newly introduced function.

Which issues(s) does this PR fix?

N/A

Other notes for review

• No semantics changed, just refactoring of the code to match closer to the specs.

[codecov]

Codecov Report

Merging #8741 (a82d28a) into develop (5217081) will decrease coverage by 15.71%.
The diff coverage is 77.77%.

@@             Coverage Diff              @@
##           develop    #8741       +/-   ##
============================================
- Coverage    61.51%   45.79%   -15.72%     
============================================
  Files          509      480       -29     
  Lines        34789    33390     -1399     
============================================
- Hits         21400    15291     -6109     
- Misses       10219    15535     +5316     
+ Partials      3170     2564      -606     

[terencechain]

LGTM!