[llvm-branch-commits] [CI] Generate Test Report With No Test Results (PR #147871)

[Aiden Grossman via llvm-branch-commits]

https://github.com/boomanaiden154 created https://github.com/llvm/llvm-project/pull/147871

This patch makes it so that generate_test_report_github.py generates a
test report even when we don't get any test results. This otherwise
created a pretty confusing user experience on the Github side if the
build failed before any tests ran or in cases like running check-libc
where none of the tests are run through lit.