False positives when using white space around = in f-string debug format.

[WarrenWeckesser]

With this file:

x = 123
print(f'{ x = }')

pycodestyle 2.12.1 gives this output:

$ pycodestyle -v foo.py 
checking foo.py
foo.py:2:10: E201 whitespace after '{'
foo.py:2:12: E251 unexpected spaces around keyword / parameter equals
foo.py:2:14: E202 whitespace before '}'
foo.py:2:14: E251 unexpected spaces around keyword / parameter equals

Those spaces should not be reported as problems. Spaces in front of x and around = in that string are significant. The = format was designed and implemented to allow such spaces. To quote from python/cpython#80998,

Finally, and this is the best part: what if you want whitespace around
the equals sign? Well, to the left is no problem; whitespace is preserved
from the original text inside the curly braces:
f"{ chr(65) =}" => " chr(65) ='A'"
But we also explicitly permit, and preserve, whitespace after the
equals sign:
f"{chr(65) = }" => "chr(65) = 'A'"

[asottile]

please search for duplicates!