The test runner used `&>>` to channel stderr to stdout and append
all that to a file. However, that's Bash 4 syntax, which is not
available everywhere, e.g., on MacOS. Bash pre-4 syntax requires
the classic `>>file 2>&1` notation.
This commit rewrites the test runner to use the portable syntax.
Moreover, it also rewrites `&>` to `>file 2>&1` for the sake of
consistency.
JerryScript-DCO-1.0-Signed-off-by: Akos Kiss akiss@inf.u-szeged.hu
8ed5078e96