Don't download twice codecov in coverage_build.yml

[vvaltchev]

Currently, https://uploader.codecov.io/latest/linux/codecov is downloaded twice: once by the command ./build/scripts/generate_kernel_coverage_report --codecov and once explicitly. It would be better to skip the 2nd download and just re-run the coverage tool from ./build/tmp/covecov.

@michelececcacci I guess this is for you to fix ;-)

[michelececcacci]

I can take it, no problem!

[vvaltchev]

Thanks @michelececcacci !! :-)

[vvaltchev]

Thanks!!