Previously, the loadtest would always compare against main and the
latest tag. This meant a loadtest running on the v13 release branch,
would compare to a *future* version of both. This is not useful, and
also not supported by `postgrest-loadtest-against`, which recently
introduced a change on `main`, that now breaks the tests on the back
branches.
With this change, the loadtest will always run against the current
target branch of a PR, so against the v13 branch for a PR against v13,
for example. Also, it will compare against the latest released tag *for
that branch*.
Thus, when running this for v12, it will test against the v12 branch and
the v12.2.12 tag.
Wolfgang Walther
4a16dd924b