Due to #24409 , we can now specify '--not' when getting all commits from
a repo to exclude commits from a different branch.
When I wrote that PR, I forgot to also update the code that counts the
number of commits in the repo. So now, if the --not option is used, it
may return too many commits, which can indicate that another page of
data is available when it is not.
This PR passes --not to the commands that count the number of commits in
a repo
ff5629268c