Allow new version of x509 for Erlang 28.0.1 and higher

[Hermanverschooten]

Hey Saša,

When I tried to upgrade to Erlang 28.0, compilation failed on x509, voltone/x509#86
This was solved in 28.0.1 and x509 0.9.
Currently the version of x509 is locked to 0.8.8.
x509 should be backward compatible.

Herman

[sasa1977]

Thanks, a PR would be appreciated :-)

[Hermanverschooten]

I just made the PR #75 but the tests fail in the GH action, while they do pass on my machine.

[sasa1977]

These tests have been flaky for sometime, I think something changed in some OTP version which leads to some race conditions in test. I was never able to figure it out completely. Anyway, merged it, thanks!