Add dpt-hybrid support (#20645)

* add `dpt-hybrid` support

* refactor

* final changes, all tests pass

* final cleanups

* final changes

* Apply suggestions from code review

Co-authored-by: Patrick von Platen <patrick.v.platen@gmail.com>

* fix docstring

* fix typo

* change `vit_hybrid` to `hybrid`

* replace dataclass

* add docstring

* move dataclasses

* fix test

* add `PretrainedConfig` support for `backbone_config`

* fix docstring

* Apply suggestions from code review

Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>

* remove `embedding_type` and replace it by `is_hybrid`

Co-authored-by: Patrick von Platen <patrick.v.platen@gmail.com>
Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>

tests/models/dpt/test_modeling_dpt.py

@@ -61,6 +61,7 @@ class DPTModelTester:
         attention_probs_dropout_prob=0.1,
         initializer_range=0.02,
         num_labels=3,
+        is_hybrid=False,
         scope=None,
     ):
         self.parent = parent
@@ -81,6 +82,7 @@ class DPTModelTester:
         self.initializer_range = initializer_range
         self.num_labels = num_labels
         self.scope = scope
+        self.is_hybrid = is_hybrid
         # sequence length of DPT = num_patches + 1 (we add 1 for the [CLS] token)
         num_patches = (image_size // patch_size) ** 2
         self.seq_length = num_patches + 1
@@ -111,6 +113,7 @@ class DPTModelTester:
             attention_probs_dropout_prob=self.attention_probs_dropout_prob,
             is_decoder=False,
             initializer_range=self.initializer_range,
+            is_hybrid=self.is_hybrid,
         )
 
     def create_and_check_model(self, config, pixel_values, labels):