fix en docs of some Apis (gradients, scope_guard, cuda_places, name_scope, device_guard, load_program_state, scale, ParamAttr and WeightNormParamAttr) (#41604)

* Update scope_guard; test=document_fix

* gradients; test=document_fix

* gradients; test=document_fix

* name_scope; test=document_fix

* cpu_places; test=document_fix

* WeightNormParamAttr; test=document_fix

* cuda_places; test=document_fix

* load_program_state; test=document_fix

* device_guard; test=document_fix

* device_guard; test=document_fix

* ParamAttr; test=document_fix

* scale; test=document_fix

* scale; test=document_fix

* update code example；test=document_fix
Co-authored-by: NChen Long <1300851984@qq.com>

* fix DLTP-15151, paddle.ParamAttr API

* fix DLTP-15083/DLTP-15274, paddle.nn.functionl.assign paddle.cast API

* fix DLTP-15431/DLTP-15432, paddle.static.nn.conv2d paddle.static.nn.conv2d_transpose API

* fix DLTP-15083, paddle.nn.functionl.assign API

* fix DLTP-15431/DLTP-15432, paddle.static.nn.conv2d paddle.static.nn.conv2d_transpose API

* support in_dygraph_mode for cast op, test=develop

* fix bug,test=develop

* fix doc

* fix DLTP-15431/DLTP-15432, paddle.static.nn.conv2d paddle.static.nn.conv2d_transpose API

* Fix api docs in RNN, Transformer, layer_norm, WeightNormParamAttr.
test=develop

* Fix api doc for print in label_smooth.
test=develop

* Update api docs according to review comments.
Add name argument in RNN back.
test=develop

* upgrade comment string to raw string

* fix string in

* fix string with ' '

* revert update on comments

* upgrade only necessary

* fix sample code checker

* fix comments with '''

* Change docs of WeightNormParamAttr to dygraph model, test=develop, test=document_fix

* add weight_norm, test=develop

* enhance attention_lstm and param_attr error message
* fix: fix param_attr type check

梯度裁剪的策略进行了升级，配合修复相应的 裁剪API、minimize、ParamAttr 的API英文文档。

对应API变动的文档： #23224 

对应中文文档PR：PaddlePaddle/FluidDoc#1942

* support dygraph structured name; test=develop

* add load static param unitest and fix save load; test=develop

* fix varBase import error; test=develop

* fix unitest error; test=develop

* add comment for parameter; test=develop

* fix uni test error; test=develop

* change parallel se-resnet; test=develop

* fix dygraph se resnext parallel test; test=develop

* remove useless code; test=develop

* remove useless code; test=develop

* modify WeightNormParamAttr English doc test=develop

* fix en docs of apis, test=develop, test=document_fix

* follow chunwei's comments, test=develop

* Fix arg do_model_average in param_attr

test=develop

* Update api spec

test=develop

* fix g_param shape mismatch in WeightNormParamAttr

* add comment to show why insert reshape in startup_program
test=develop

* fix api doc according to the reviewer's comment test=develop

* fix api format and examples

test=develop

* Update executor.py

test=develop

* Update nn.py

* Update nn.py

test=develop

* Update nn.py

test=develop

1. Add attr 'average' into ParamAttr.
2. Make 'params_grads' optional for AverageModel.
3. Add option 'average_mean' and 'average_variance' for batch_normal.