Resolve the directory where suite summary artifacts are written and read.
Honors PHOENIX_TEST_REPORT_DIR_ENV_VAR when set. Otherwise it derives
a directory under the OS temp dir, namespaced by a hash of the current
working directory so that concurrent test runs in different projects don't
read each other's artifacts.
Resolve the directory where suite summary artifacts are written and read.
Honors PHOENIX_TEST_REPORT_DIR_ENV_VAR when set. Otherwise it derives a directory under the OS temp dir, namespaced by a hash of the current working directory so that concurrent test runs in different projects don't read each other's artifacts.