The default runtime for CIFuzz[1] is 600 seconds; use it.
Since GitHub pull-requests are not the main contribution workflow the
number of runs should be manageable.
[1]: https://google.github.io/oss-fuzz/getting-started/continuous-integration/
Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Fail and report unreproducible fuzzing crashes and leaks. Such failures
are probably related to some global state not properly reset in the
fuzzer and can cause OSS-Fuzz to report flaky issues.
Suggested-by: Evgeny Vereshchagin
Signed-off-by: Christian Göttsche <cgzones@googlemail.com>