Add PythonFunctionComponent and test case for it

tests/text_experimental_components.py

@@ -0,0 +1,15 @@
+from langflow.components import experimental
+
+
+def test_python_function_component():
+    # Arrange
+    python_function_component = experimental.PythonFunctionComponent()
+
+    # Act
+    # function must be a string representation
+    function = "def function():\n    return 'Hello, World!'"
+    # result is the callable function
+    result = python_function_component.build(function)
+
+    # Assert
+    assert result() == "Hello, World!"