build: fix pydantic version due to bug

requirements.txt

@@ -1,3 +1,8 @@
-click>=7.1.2
-requests>=2.25.1
-gradio==4.37.2
+click >= 7.1.2  # dont fix upper version because conflict with typer installed by gradio
+requests >= 2.25.1, < 3.0
+gradio == 4.37.2
+pydantic == 2.7.1
+# Pydantic is installed by Gradio (pydantic>=2.0)
+# it seems that newer versions of Pydantic (2.9.2) throws errors [1] with some modules (eg. corals)
+# So we fix the version till we have more time to debug+update
+# [1]: pydantic.errors.PydanticSchemaGenerationError: Unable to generate pydantic-core schema for <class 'starlette.requests.Request'>. Set `arbitrary_types_allowed=True` in the model_config to ignore this error or implement `__get_pydantic_core_schema__` on your type to fully support it.