[Zero-Dim] support input 0D Tensor for fmax/fmin/complex api (#49730)

* [Zero-Dim] support input 0D Tensor for maximum,minimum,allclose,sigmoid_focal_loss

* [Zero-Dim] add backward test for sigmoid_focal_loss with 0-D input Tensor

* [Zero-Dim] support input 0D Tensor for fmax,fmin,complex

python/paddle/fluid/tests/unittests/test_zero_dim_tensor.py

@@ -285,6 +285,9 @@ binary_api_list = [
     paddle.logical_xor,
     paddle.maximum,
     paddle.minimum,
+    paddle.fmax,
+    paddle.fmin,
+    paddle.complex,
 ]
 
 binary_int_api_list = [