[xdoctest][task 120] Reformat example code with google style in...

[xdoctest][task 120] Reformat example code with google style in python/paddle/quantization/observers/abs_max.py (#56231)
Co-authored-by: NNyakku Shigure <sigure.qaq@gmail.com>

python/paddle/quantization/observers/abs_max.py

@@ -30,12 +30,12 @@ class AbsmaxObserver(ObserverFactory):
             For details, please refer to :ref:`api_guide_Name`. Default is None.
 
     Examples:
-       .. code-block:: python
+        .. code-block:: python
 
-            from paddle.quantization import QuantConfig
-            from paddle.quantization.quanters import FakeQuanterWithAbsMaxObserver
-            quanter = FakeQuanterWithAbsMaxObserver(moving_rate=0.99)
-            q_config = QuantConfig(activation=quanter, weight=quanter)
+            >>> from paddle.quantization import QuantConfig
+            >>> from paddle.quantization.quanters import FakeQuanterWithAbsMaxObserver
+            >>> quanter = FakeQuanterWithAbsMaxObserver(moving_rate=0.99)
+            >>> q_config = QuantConfig(activation=quanter, weight=quanter)
     """
 
     def __init__(self, quant_bits=8):