refine optimizer name doc, test=release/1.6, test=document_fix (#20096)

paddle/fluid/API.spec

@@ -980,7 +980,7 @@ paddle.fluid.optimizer.RMSPropOptimizer.backward (ArgSpec(args=['self', 'loss',
 paddle.fluid.optimizer.RMSPropOptimizer.get_opti_var_name_list (ArgSpec(args=['self'], varargs=None, keywords=None, defaults=None), ('document', '6adf97f83acf6453d4a6a4b1070f3754'))
 paddle.fluid.optimizer.RMSPropOptimizer.load (ArgSpec(args=['self', 'stat_dict'], varargs=None, keywords=None, defaults=None), ('document', '649a92cf7f1ea28666fd00c4ea01acde'))
 paddle.fluid.optimizer.RMSPropOptimizer.minimize (ArgSpec(args=['self', 'loss', 'startup_program', 'parameter_list', 'no_grad_set', 'grad_clip'], varargs=None, keywords=None, defaults=(None, None, None, None)), ('document', 'b15cffad0903fc81af77a0580ceb2a9b'))
-paddle.fluid.optimizer.AdadeltaOptimizer ('paddle.fluid.optimizer.AdadeltaOptimizer', ('document', 'e132700f81e9c5d27a7b3cd32b38d714'))
+paddle.fluid.optimizer.AdadeltaOptimizer ('paddle.fluid.optimizer.AdadeltaOptimizer', ('document', 'f4354aef5e3b9134fa68919b75a3a097'))
 paddle.fluid.optimizer.AdadeltaOptimizer.__init__ (ArgSpec(args=['self', 'learning_rate', 'epsilon', 'rho', 'regularization', 'name'], varargs=None, keywords=None, defaults=(1e-06, 0.95, None, None)), ('document', '6adf97f83acf6453d4a6a4b1070f3754'))
 paddle.fluid.optimizer.AdadeltaOptimizer.apply_gradients (ArgSpec(args=['self', 'params_grads'], varargs=None, keywords=None, defaults=None), ('document', '80ea99c9af7ef5fac7e57fb302103610'))
 paddle.fluid.optimizer.AdadeltaOptimizer.apply_optimize (ArgSpec(args=['self', 'loss', 'startup_program', 'params_grads'], varargs=None, keywords=None, defaults=None), ('document', '5c46d1926a40f1f873ffe9f37ac89dae'))

python/paddle/fluid/optimizer.py

@@ -1804,7 +1804,9 @@ class AdadeltaOptimizer(Optimizer):
         regularization (WeightDecayRegularizer, optional): A Regularizer, such as
                 fluid.regularizer.L2DecayRegularizer. Default None, meaning that there is no
                 regularization.
-        name (str, optional): A optional name prefix for debugging. Default None.
+        name (str, optional): The default value is None. Normally there is no need for user
+                to set this property. For more information, please refer to
+                :ref:`api_guide_Name` .
 
     Examples:
         .. code-block:: python