[Docs] Fix spelling and grammar mistakes (#28825)

* Fix typos and grammar mistakes in docs and examples

* Fix typos in docstrings and comments

* Fix spelling of `tokenizer` in model tests

* Remove erroneous spaces in decorators

* Remove extra spaces in Markdown link texts

examples/research_projects/wav2vec2/run_common_voice.py

@@ -69,12 +69,12 @@ class ModelArguments:
     hidden_dropout: Optional[float] = field(
         default=0.1,
         metadata={
-            "help": "The dropout probabilitiy for all fully connected layers in the embeddings, encoder, and pooler."
+            "help": "The dropout probability for all fully connected layers in the embeddings, encoder, and pooler."
         },
     )
     feat_proj_dropout: Optional[float] = field(
         default=0.1,
-        metadata={"help": "The dropout probabilitiy for all 1D convolutional layers in feature extractor."},
+        metadata={"help": "The dropout probability for all 1D convolutional layers in feature extractor."},
     )
     mask_time_prob: Optional[float] = field(
         default=0.05,