Update KLFitter to v1.3.2

It's been a while, but here's another update of KLFitter. This MR changes the version from 1.2.0 to 1.3.2, which includes quite a few updates. The full list of changes is on github, here for v1.3.0, here for v1.3.1 and here for v1.3.2. Or maybe the version diff is more comprehensive. I compiled atlasexternals with the new version of KLFitter, just before the LCG and ROOT updates went in last week. With the old LCG/ROOT it worked without problems, but I had trouble compiling ROOT 6.16, apparently because of some outdated SQL libraries (?) that are needed in ROOT's data frame code now.

Either way, compiling atlasexternals with KLFitter just before that update works without problems, as does compiling AnalysisTop and linking it against it. So I think the CI should run through smoothly as well.