…ax seats

Max seats from prioriy & fairness work estimator is now min(0.15 x
nominalCL, nominalCL/handSize)

'Max seats' calculated by work estimator is currently hard coded to 10.
When using lower values for --max-requests-inflight, a single
LIST request taking up 10 seats could end up using all if not most seats in
the priority level. This change updates the default work estimator
config such that 'max seats' is at most 10% of the
maximum concurrency limit for a priority level, with an upper limit of 10.
This ensures seats taken from LIST request is proportional to the total
available seats.

Signed-off-by: Andrew Sy Kim <andrewsy@google.com>