[benchmarks] Set smoke test to Startup benchmark and shorten long running benchmarks.
[benchmarks] Set smoke test to Startup benchmark and shorten long running benchmarks.

The smoke test runs ffmpeg, which is a few orders of magnitude longer than the startup benchmark.

Adding --test.benchtime=1ns ensures long running benchmarks only run once when benchmarks are calculating
b.N.

PiperOrigin-RevId: 434526626

google/gvisor,google/gvisor,google/gvisor,google/gvisor,google/gvisor,google/gvisor,google/gvisor,google/gvisor