Bump Perl from 5.40 to 5.42. Remove some older versions from the CI test.

[IsaacG]

Follows exercism/perl5-test-runner#98 and exercism/perl5-analyzer#46

[IsaacG]

@kotp Do you have the ability to rerun tests? And/or should some of these be dropped?

[kotp]

@kotp Do you have the ability to rerun tests?

I do.

And/or should some of these be dropped?

5.38 is EOL July 2nd of this year, and anything lower, we probably should not be testing for automatically.

So am for removing 5.38 via a logic switch, maybe. (A functional conditional no-op after a date query)

And of course, testing for EOL versions seems to be not all that valuable for what we are doing.

[IsaacG]

MacOS tests were fine for #734 but started timing out on #735

[kotp]

Small change.

Also, we should look into the files not stating "use version" but use the version that is available instead,

[kotp]

@IsaacG I can bring this in regardless of the failing tests which currently target MacOS.

We can fix the CI in a different PR.

[IsaacG]

@IsaacG I can bring this in regardless of the failing tests which currently target MacOS.

We can fix the CI in a different PR.

Sounds good to me. I don't have a Mac so I'm not planning on debugging this MacOS issue. I don't have merge permissions for this PR.