lcov fails with code error == 0

[dajose]

This line is wrong https://github.com/kuralabs/flowbber/blob/master/lib/flowbber/plugins/sources/lcov.py#L263

As there are cases where lcov fails, yet the code is 0

$ lcov --rc lcov_branch_coverage=1 --directory /foo/ -capture --output-file /tmp/tmp8hlgxlg7
Capturing coverage data from /foo/
Found gcov version: 5.4.0
Scanning /foo/ for .gcda files ...
geninfo: WARNING: no .gcda files found in /foo/ - skipping!
Finished .info-file creation
$ echo $?
0