fix: prevent mutation of global PROVIDERS list in Factory.create

[GitMike01]

What does this change

Changed the way providers and includes are combined in Factory.create to ensure the original list is not modified

What was wrong

The code was using the in-place addition operator (+=) on the providers list. When providers defaulted to the global PROVIDERS constant, this operator mutated the global list itself. This caused side effects where subsequent Faker instances would unexpectedly contain providers from previous instances

How this fixes it

Replaced the in-place operator += with the concatenation operator +. This creates a new list for the local scope of the function, leaving the global PROVIDERS constant intact and preventing unintended side effects.

Fixes #2311

AI Assistance Disclosure (REQUIRED)

• No AI tools were used in preparing this PR.
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Checklist

• I have read the documentation about CONTRIBUTING
• I have read the documentation about Coding style
• I have run make lint

[fcurella]

I think the AI might be hallucinating here. I don't see how the change would prevent mutation. If it does, please add a comment explaining.

[fcurella]

Duplicate of #2313