feat: added fft2

[jaskiratsingh2000]

Closes: #19052 of #15047

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[jaskiratsingh2000]

@DecFox For same same reason the lint is throwing the formatting error for a line. I have corrected it multiple times even then. Can you please check once?
@DecFox

[jieunboy0516]

Hi @jaskiratsingh2000 , thanks for your contribution to Ivy. Your code looks good to me but I am currently unable to run the unit tests due to a "key error: cpu not found" issue. I will wait for awhile until the issue gets fixed and will return to you to confirm the unit tests are passing!

[jieunboy0516]

Sorry @jaskiratsingh2000, turns out there is some issue in your code

    |     fft_first_axis = fft(x, n=s[0] if s else None, axis=axes[0], norm=norm)
    | TypeError: 'int' object is not subscriptable

that is causing the unit tests to fail. Could you please take a look and fix it? Thx!