coverage: upload report

[junr03]

Description: installs lcov in order to generate coverage reports once again.
Fixes #1009

Signed-off-by: Jose Nino [email protected]

[junr03]

@goaway I am not sure why the coverage test is still passing. I realized that after merging all the platform_bridge code coverage should have dropped. My local coverage run is failing with:

Overall coverage rate:
  lines......: 79.9% (650 of 814 lines)
  functions..: 68.6% (70 of 102 functions)
Code coverage 79.9 is lower than limit of 96.5

as I would expect. This PR should let us see what is going on with the coverage run in CI

[junr03]

@goaway relatedly, I know the main way you want to test the platform bridge filter is with #995. But I think we can also write a unit test suite with simple c++ implementation of a "platform" api.

[junr03]

Ah I see: https://github.com/lyft/envoy-mobile/pull/999/checks?check_run_id=942636509#step:4:996

[junr03]

@goaway ok now I see in CI what I see locally as well: https://github.com/lyft/envoy-mobile/pull/999/checks?check_run_id=942878705#step:4:1028.

Do you mind writing tests to improve coverage?

[junr03]

Blocked by #1008

[junr03]

fixed in #1014