Update Asanpardakht driver (#180)

[Mohammadreza-73]

• Handle paymeny currency (Rial, Toman)

Description

Add currency in payment config for Asanpardakht driver.

Motivation and context

Why is this change required? What problem does it solve?
I handle currency in Rial and with Asanpardakht driver, multiply 10 to convert amout to Rial!

If it fixes an open issue, please link to the issue here (if you write fixes #180
or closes #180, the issue will be automatically closed when the pull is accepted.)

Types of changes

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• 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 change)

Checklist:

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[Mohammadreza-73]

طبق issue #180 ، در درایور آسان پرداخت مبلغی که من خودم به ریال دارم در عدد 10 ضرب می شود.

برای مدیریت این کار میشه طبق این PR برای کانفیگ درایورها مقدار currency هم مشخص نمود.
این مقدار بیانگر واحد مالی هست که توسعه دهنده در برنامه خود از آن استفاده می کند.

[Mohammadreza-73]

اگر با این روش موافق هستید میشه برای کانفیگ هر درایور currency را مشخص نمود.
یا اینکه یک کانفیگ کلی برای این کار داشته باشیم.

return [
    // Default Driver
    'default' => 'zarinpal',
    'currency' => 'T'  // Can be R, T
]

[parsariyahi]

مرسی که انجام دادی.