`--timeout` is ignored by `deqp-runner suite`

I'm adding DEQP_RUNNER_OPTIONS: '--timeout 300' to two jobs, one that uses a suite, and one that doesn't.

The latter gets the timeout correctly increased, but the former doesn't, although I can see in both job logs that the variable was expanded correctly.

As a workaround I'm now putting timeout = 300 in the deqp-*.toml.