If you look at some of the output, you'll see that travis is, for instance, it's not actually testing 5.8.7. If you look closer, I think you'll find that nothing below 5.14 is currently being smoked in Travis.
The job you linked is indeed testing 5.8.7. See at line 232 of the output it actually compiles that perl first, and then at line 245 prints the perl -V output which is correct.
If you look at some of the output, you'll see that travis is, for instance, it's not actually testing 5.8.7. If you look closer, I think you'll find that nothing below 5.14 is currently being smoked in Travis.
https://travis-ci.org/github/Perl-Toolchain-Gang/ExtUtils-MakeMaker/jobs/712741735
I can provide you a .github CI if you prefer that would look something like this https://github.com/toddr/IPC-Run/tree/master/.github/workflows
Note that it only tests 5.8, not 5.8.7