Update upload mechanism for code coverage

[fintarin]

• Read PR documentation
• Update changelog
• Update documentation

Close #377, close #415, close #410

[codecov]

Codecov Report

Merging #416 (aa48535) into master (84c2b74) will increase coverage by 5.27%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #416      +/-   ##
==========================================
+ Coverage   58.46%   63.73%   +5.27%     
==========================================
  Files         210      211       +1     
  Lines       11377    13546    +2169     
==========================================
+ Hits         6651     8634    +1983     
- Misses       4726     4912     +186     

Flag	Coverage Δ
unittests	63.73% <ø> (?)

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Impacted Files	Coverage Δ
sc-memory/sc-memory/sc_addr.cpp	88.88% <0.00%> (-2.42%)	⬇️
sc-memory/sc-memory/sc_event.cpp	84.61% <0.00%> (-2.35%)	⬇️
sc-memory/sc-memory/utils/sc_log.cpp	73.17% <0.00%> (-1.83%)	⬇️
tools/codegen/Parser/Cursor.cpp	89.13% <0.00%> (-1.78%)	⬇️
tools/builder/src/main.cpp	82.05% <0.00%> (-1.74%)	⬇️
sc-memory/sc-memory/sc_object.cpp	71.42% <0.00%> (-1.30%)	⬇️
sc-memory/sc-core/sc-store/sc_element.c	57.14% <0.00%> (-1.20%)	⬇️
tools/codegen/Parser/Sha256.cpp	98.87% <0.00%> (-1.13%)	⬇️
sc-memory/sc-memory/sc_template_generate.cpp	80.00% <0.00%> (-0.24%)	⬇️
sc-server/src/main.cpp	0.00% <0.00%> (ø)
... and 151 more

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