Laravel 10 support

[jasonvarga]

Summary

This PR adds Laravel 10 support.

• Updates dependencies
• Updates GitHub Action workflows
• The only failing tests had to do with validation strings, which have changed slightly in Laravel 10. I've updated the tests to use lang() helper instead of the strings

Only issue is code analysis:

PHPStan is now failing. This is a little over my head. I had to require v2 of larastan in order for Laravel 10 to be installable. I removed the phpstan explicit requirement so larastan can deal with that. Maybe that's why it's failing. Or maybe it has to do with all the typehints added to Laravel 10.

I noticed in this commit that you required explicit versions. Not sure of the story behind that.

From my end, this PR is done / ready for review. Let me know what you want done regarding Larastan/PHPStan.

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Type of change:

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update
• Misc. change (internal, infrastructure, maintenance, etc.)

Checklist:

• Existing tests have been adapted and/or new tests have been added
• Add a CHANGELOG.md entry
• Update the README.md
• Code style has been fixed via composer fix-style

[mfn]

Nice, thanks! Will try to get to it ASAP, but a bit busy this week

[jasonvarga]

No worries. Thanks!

[mfn]

LGTM, my suggested fix will be merged via #984

[mfn]

Release tagged! https://github.com/rebing/graphql-laravel/releases/tag/8.6.0