Ability to customize credential keys e.g: email/username

[daniel-de-wit]

Closes #76

A new section is added to config/lighthouse-sanctum.php which allows for custom user identification field to be used when authenticating.

For example, using username instead of the default email.

/*
|--------------------------------------------------------------------------
| Identification
|--------------------------------------------------------------------------
|
| Configure the credential fields by which the user will be identified.
| Default: email
*/

'user_identifier_field_name' => 'username',

Update the GraphQL schema accordingly

input LoginInput {
    username: String! @rules(apply: ["required"])
}

[coveralls]

Pull Request Test Coverage Report for Build 2527314905

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 4 of 4 (100.0%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.02%) to 99.541%

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Totals
Change from base Build 1940564576:	0.02%
Covered Lines:	217
Relevant Lines:	218

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💛 - Coveralls