[Dy2stat] Add Test and Example Code for Different Access to ProgramTranslator and Fix Related Bug (#23958) (#23963)

Cherry pick of 23958

1. Rename Dygraph To Static Decorators to declarative
2. dygraph_to_static_func is still using in some training tests, I cannot delete it now.
3. Add some API docs

* [Cherry-pick Release/2.0] remove redundant visit func, test=develop (#23877)

* [Cherry-pick Release/2.0] [dy2static]Fix a bug of is_dygraph_api and move BasicApiTransformer to a separate file(#23923)

* Move BasicApiTransformer to a separate file. test=develop

* Fix a bug: A api in module is not a real dygraph api in dygraph_to_static. test=develop
Co-authored-by: NChen Weihang <chenweihang@baidu.com>

* Avoid logging.info be printed many times in dygraph_mode,test=develop

* Avoid logging.info be printed many times in dygraph_mode,test=develop

* OP clip, merge_lod_tensor, convert/elementwise error message enhancement. test=develop

* add addcmul, test=release/2.0

* enhance attention_lstm and param_attr error message

* test=develop fix api doc error

test=release/2.0

* Fix judge pslib transpiler cherry-pick (#23720)

[cherry pick] fix sample code diff for OP(retinanet_detection_output, retinanet_target_assign), fix  default value for OP(sigmoid_focal_loss) (#23744). test=release/2.0-beta (#23858)

Fix the support the float16 of scale op, add delete the raise case for fp16

* add approximation for gelu, test=develop

* add functional conv

* add test and doc for function convs, test=develop

* update ConvTransposeOp's InferShape and error message, test=develop

* add hsigmoid, row_conv in paddle.nn(functional and layer), test=develop

* fix hyperlinks in docstring

* correct reader device index, test=develop

* fix async executor scope var initialization, test=release/2.0

* Add variance computing layer for tensor

* Format input data types

* Remove unnecessary expand operation

* Some fixes in doc

add new tensor: max,min,t,eye,log1p; test=develop

* lod_tensor_to_array error message enhance. test=develop

* api compild program error polish, test=develop

* fix coverage problem, test=develop

* fix details & add unittests, test=develop

* add test for coverage, test=develop

* Add new API : randn

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* Add new API : randn

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* Add new API : randn

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* Add new API : randn

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* aAdd new API : randn

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* Add new API : randn

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* Add new API : randn

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* Add new API : randn

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* Add new API : randn

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* Add new API : randn

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* Add new API : randn

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* Add new API : randn

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In those ops, some api has execute run error, fix those op, and format some sample code.

raw doc: bool, float15, float32, float64, int8, int32, int64, uint8.
new doc: bool, float16, float32, float64, int8, int32, int64, uint8. 

* Add the support of bool list for assign value, test=develop

* Fix the assign op test case for bool dtype, test=develop

* Revert to usage of 'assign' in test_transformer. test=develop
Co-authored-by: Nwawltor <fangzeyang0904@hotmail.com>

* Add the support of bool list for assign value, test=develop
* Fix the assign op test case for bool dtype, test=develop

* Add new norm api, support frobenius norm and p-order vector norm. test==develop
* combine test files, add more attr checks. test=develop

* add unit accessor in fleet, support DownpourUnitAccessor
* test=develop

* add cuda kernel for seed, test=develop

* polish error message, test=develop

* error message enhance for clip_by_norm. test=develop

* fix clip_by_norm. test=develop

* fix clip error message. test=develop

* fix if logic in dygraph, test=develop

* fix bug, test=develop

* enhance error msg. test=develop

* print invalid argment

* update comment, test=develop

* fix enforce not meet specification

* fix enforce not meet specification, test=develop