fix(cov): exclude generated files

Generated files like protobuf bindings are not required to be checked
for test coverage. This commit removes the coverage statistics for these
files from `coverage.out` after merging coverage results.

Signed-off-by: Prajwal S N <prajwalnadig21@gmail.com>

test/Makefile

@@ -104,6 +104,8 @@ coverage: check-go-version $(COVERAGE_BINARIES) $(TEST_PAYLOAD)
 	# combine the coverage results to show up in GitHub.
 	cat .coverage/coverprofile* | \
 		grep -v mode: | sort -r | awk '{if($$1 != last) {print $$0;last=$$1}}' >> ${COVERAGE_PATH}/coverage.out
+	# We do not want to upload coverage for autogenerated files (*.pb.go)
+	sed -i '/\.pb\.go/d' ${COVERAGE_PATH}/coverage.out
 
 codecov:
 	curl -Os https://uploader.codecov.io/latest/linux/codecov