Add link to CPY Essentials Learn guide for storage module

Author: tekktrik

shared-bindings/storage/__init__.c

@@ -40,7 +40,12 @@
 //| The `storage` provides storage management functionality such as mounting and
 //| unmounting which is typically handled by the operating system hosting Python.
 //| CircuitPython does not have an OS, so this module provides this functionality
-//| directly."""
+//| directly.
+
+//| For more information regarding using the `storage` module, refer to the CircuitPython
+//| Essentials Learn guide:
+//| https://learn.adafruit.com/circuitpython-essentials/circuitpython-storage
+//| """
 //|
 
 //| def mount(filesystem: VfsFat, mount_path: str, *, readonly: bool = False) -> None: