Add TFConvNextModel (#15750)

* feat: initial implementation of convnext in tensorflow.

* fix: sample code for the classification model.

* chore: added checked for  from the classification model.

* chore: set bias initializer in the classification head.

* chore: updated license terms.

* chore: removed ununsed imports

* feat: enabled  argument during using drop_path.

* chore: replaced tf.identity with layers.Activation(linear).

* chore: edited default checkpoint.

* fix: minor bugs in the initializations.

* partial-fix: tf model errors for loading pretrained pt weights.

* partial-fix: call method updated

* partial-fix: cross loading of weights (4x3 variables to be matched)

* chore: removed unneeded comment.

* removed playground.py

* rebasing

* rebasing and removing playground.py.

* fix: renaming TFConvNextStage conv and layer norm layers

* chore: added initializers and other minor additions.

* chore: added initializers and other minor additions.

* add: tests for convnext.

* fix: integration tester class.

* fix: issues mentioned in pr feedback (round 1).

* fix: how output_hidden_states arg is propoagated inside the network.

* feat: handling of  arg for pure cnn models.

* chore: added a note on equal contribution in model docs.

* rebasing

* rebasing and removing playground.py.

* feat: encapsulation for the convnext trunk.

* Fix variable naming; Test-related corrections; Run make fixup

* chore: added Joao as a contributor to convnext.

* rebasing

* rebasing and removing playground.py.

* rebasing

* rebasing and removing playground.py.

* chore: corrected copyright year and added comment on NHWC.

* chore: fixed the black version and ran formatting.

* chore: ran make style.

* chore: removed from_pt argument from test, ran make style.

* rebasing

* rebasing and removing playground.py.

* rebasing

* rebasing and removing playground.py.

* fix: tests in the convnext subclass, ran make style.

* rebasing

* rebasing and removing playground.py.

* rebasing

* rebasing and removing playground.py.

* chore: moved convnext test to the correct location

* fix: locations for the test file of convnext.

* fix: convnext tests.

* chore: applied  sgugger's suggestion for dealing w/ output_attentions.

* chore: added comments.

* chore: applied updated quality enviornment style.

* chore: applied formatting with quality enviornment.

* chore: revert to the previous tests/test_modeling_common.py.

* chore: revert to the original test_modeling_common.py

* chore: revert to previous states for test_modeling_tf_common.py and modeling_tf_utils.py

* fix: tests for convnext.

* chore: removed output_attentions argument from convnext config.

* chore: revert to the earlier tf utils.

* fix: output shapes of the hidden states

* chore: removed unnecessary comment

* chore: reverting to the right test_modeling_tf_common.py.

* Styling nits

Co-authored-by: ariG23498 <aritra.born2fly@gmail.com>
Co-authored-by: Joao Gante <joao@huggingface.co>
Co-authored-by: Sylvain Gugger <Sylvain.gugger@gmail.com>

docs/source/index.mdx

@@ -179,7 +179,7 @@ Flax), PyTorch, and/or TensorFlow.
 |           Canine            |       ✅       |       ❌       |       ✅        |         ❌         |      ❌      |
 |            CLIP             |       ✅       |       ✅       |       ✅        |         ✅         |      ✅      |
 |          ConvBERT           |       ✅       |       ✅       |       ✅        |         ✅         |      ❌      |
-|          ConvNext           |       ❌       |       ❌       |       ✅        |         ❌         |      ❌      |
+|          ConvNext           |       ❌       |       ❌       |       ✅        |         ✅         |      ❌      |
 |            CTRL             |       ✅       |       ❌       |       ✅        |         ✅         |      ❌      |
 |           DeBERTa           |       ✅       |       ✅       |       ✅        |         ✅         |      ❌      |
 |         DeBERTa-v2          |       ✅       |       ❌       |       ✅        |         ✅         |      ❌      |

docs/source/model_doc/convnext.mdx

@@ -37,7 +37,8 @@ alt="drawing" width="600"/>
 
 <small> ConvNeXT architecture. Taken from the <a href="https://arxiv.org/abs/2201.03545">original paper</a>.</small>
 
-This model was contributed by [nielsr](https://huggingface.co/nielsr). The original code can be found [here](https://github.com/facebookresearch/ConvNeXt).
+This model was contributed by [nielsr](https://huggingface.co/nielsr). TensorFlow version of the model was contributed by [ariG23498](https://github.com/ariG23498),
+[gante](https://github.com/gante), and [sayakpaul](https://github.com/sayakpaul) (equal contribution). The original code can be found [here](https://github.com/facebookresearch/ConvNeXt).
 
 ## ConvNeXT specific outputs
 
@@ -63,4 +64,16 @@ This model was contributed by [nielsr](https://huggingface.co/nielsr). The origi
 ## ConvNextForImageClassification
 
 [[autodoc]] ConvNextForImageClassification
-    - forward
+    - forward
+
+
+## TFConvNextModel
+
+[[autodoc]] TFConvNextModel
+    - call
+
+
+## TFConvNextForImageClassification
+
+[[autodoc]] TFConvNextForImageClassification
+    - call