[Bug-gsl] Small documentation bug

[Damien Desfontaines]

The diagram for gsl_ran_binomial_pdf looks wrong:
    
https://www.gnu.org/software/gsl/doc/html/randist.html#c.gsl_ran_binomial_pdf
It looks like this is a binomial distribution with n=10, not with n=9.

Cheers,

Damien