slightly alter threshold for warpAffine optimization

[fengyuentau]

Merge with opencv/opencv#25984

NewonfusionMatrixes[1] is

[[45  0  0  0  0  0  0  0  0  0]
 [ 0 57  0  0  0  0  0  0  0  0]
 [ 0  0 58  2  0  0  0  0  1  0]
 [ 0  0  0 43  0  0  0  1  0  0]
 [ 0  0  0  0 39  0  0  0  0  1]
 [ 0  0  0  1  0 49  0  0  1  0]
 [ 0  0  0  0  0  0 52  0  0  0]
 [ 0  0  1  0  0  0  0 54  0  0]
 [ 0  0  0  0  0  0  0  0 47  0]
 [ 0  1  0  1  0  0  0  0  2 44]]

which is about of pixel value 1 shift in each 4x or 5x pixel value.

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