Fix minor typos in README.md

[drbyte]

Just a few typos I noticed while reading the README.

Also added that a list of roles can also be passed as an array in addition to a collection object.

[welcome[bot]]

BOOM! Your first PR with us, thank you so much! Someone will take a look at it shortly.

Please keep in mind that:

• if this constitutes a breaking change, it might take quite a while for this to get merged; we try to emulate the Laravel release cycle as much as possible, so developers can upgrade both software once; this means a new big release every ~6 months;
• even if it's a non-breaking change, it might take a few days/weeks for the PR to get merged; unless it's a no-brainer, we like to have some community feedback on new features, before we merge them; this leads to higher-quality code, in the end; we learnt this the hard way :-)
• not all PRs get merged; sometimes we just have to hold out new features, to keep the packages lean; sometimes we don't include features that only apply to niche use cases;
• we're not perfect; if you think we're wrong, call us out on it; but in a kind way :-) we all make mistakes, best we learn from them and build better software together;

Thank you!

-- Justin Case The Backpack Robot

[jcastroa87]

Hi @drbyte thanks for your PR, will be check and merge if is approved.

Cheers.

[pxpm]

Thanks @drbyte 🙏

[welcome[bot]]

WHOOP-WHOOP! Congrats, your first PR on this repo has officialy been merged.

If you want to help out the community in other ways, you can:

• give your opinion on other Github Issues & PRs;
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Again. Thank you for the PR. You are a wonderful person. Keep 'em coming :-) Cheers!

-- Justin Case The Backpack Robot

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