Remove factory for creating int and strings

[herpaderpaldent]

This was reported here https://github.com/seatplus/seatplus/issues/2 thank you @kayl

[what-the-diff[bot]]

• Replaced the faker dependency with random_int and Str::random
• Removed unused private property $faker

[codeclimate[bot]]

Code Climate has analyzed commit e1d4a6a9 and detected 0 issues on this pull request.

The test coverage on the diff in this pull request is 100.0% (50% is the threshold).

This pull request will bring the total coverage in the repository to 88.7% (0.0% change).

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