Report jest-junit testsuite errors as failures

Test errors are different (represented differently in the JUnit XML
output from jest-junit) to test _failures_. Failures are tests
which ran and failed, errors are for tests/test suites which
did not even run because the test code itself didn't build
or didn't execute correctly.

jest-junit has an option to enable reporting of test suite errors,
but test-reporter then interprets these as successful tests.

__tests__/fixtures/test-errors/jest/files.txt

@@ -0,0 +1,3 @@
+libs/bar.spec.ts
+libs/foo.spec.ts
+tsconfig.json