Fixed lint and unit test issues.

[liamgm]

Summary of Changes

Fixed all coding style complaints raised by laravel/pint against current head 83ad0be

Fixed unit test after confirming public key string calculated by phpseclib3 is correct against python's cryptography library.

Did not fix coverage tests as I don't have a CC secret, but pcov is locally satisfied.

No functional changes, just prepping to address issue 149.

Testing

• I have added automated tests for my changes (no changes, but existing unit test was fixed)
• I ran composer test before opening this PR
• I ran composer lint-fix before opening this PR

[liamgm]

FWIW: I disagree with the most common lint failure in there that arises from this ambivalent decision.

If the maintainers agree with the alternate convention to require the empty parentheses on class instantiations without parameters, I can amend this to instead set that preference in pint.json

[liamgm]

I think this is a much nicer commit: I can create a new PR if this patch is preferable.

[dbhynds]

FWIW: I disagree with the most common lint failure in there that arises from laravel/pint#284.
If the maintainers agree with the alternate convention to require the empty parentheses on class instantiations without parameters, I can amend this to instead set that preference in pint.json

I appreciate / respect the difference of opinion. We are currently using this standard set of linting rules across multiple other projects, so I'd like to keep them consistent, rather than modifying the pint.json on this project. Either way, thank you for the PR fixing these!