Fix saturated corpus experiment requests

[ndrewh]

The parser for experiment-requests.yml checks oss_fuzz_corpus:

fuzzbench/service/automatic_run_experiment.py

Lines 64 to 67 in 421187b

	def _use_oss_fuzz_corpus(experiment_config: dict) -> bool:
	"""Returns the oss_fuzz_corpus flag of the experiment described by
	|experiment_config| as a bool."""
	return bool(experiment_config.get('oss_fuzz_corpus'))

Experiment request docs say to use oss-fuzz-corpus, not oss_fuzz_corpus

fuzzbench/service/experiment-requests.yaml

Line 9 in 421187b

# # oss-fuzz-corpus: true # Set to use latest saturated corpora from OSS-Fuzz.

and all the past experiment requests are using oss-fuzz-corpus

fuzzbench/service/experiment-requests.yaml

Lines 2273 to 2276 in 421187b

	- experiment: 2021-07-15-saturated
	description: "Benchmark a new experimental feature for AFL++ (saturated)"
	type: bug
	oss-fuzz-corpus: true

[ndrewh]

Alternatively, we could just change the yaml to use the underscore

[jonathanmetzman]

LGTM

[jonathanmetzman]

BTW note that we don't use experiment-requests.yaml. Experiments are conducted through "gcbrun" commands in PRs.

[DonggeLiu]

@ndrewh Sorry I just noticed that your commit failed the presubmit test, could you please fix it?

Thanks!