refactor(idempotency): revert helper method - restore original inline null-check pattern

Per Leandro Damascena's feedback: _get_idempotency_key_or_return_none() helper added
indirection without reducing duplication since the if None: return None check remained in all 4 callers anyway.

Restored original inline 3-line pattern in save_success, save_inprogress, delete_record, and get_record which is clearer and instantly readable.

Part of #8090

Signed-off-by: hirenkumar-n-dholariya <hirenkumarnd@gmail.com>

Author: hirenkumar-n-dholariya

aws_lambda_powertools/utilities/idempotency/persistence/base.py

@@ -136,27 +136,6 @@ def is_missing_idempotency_key(data) -> bool:
         elif isinstance(data, (int, float, bool)):
             return False
         return not data
-
-    def _get_idempotency_key_or_return_none(self, data: dict[str, Any]) -> str | None:
-        """
-        Get hashed idempotency key or return None early if key is None.
-        If the idempotency key is None, no data will be saved in the Persistence Layer.
-        See: https://github.com/aws-powertools/powertools-lambda-python/issues/2465
-
-        Parameters
-        ----------
-        data: dict[str, Any]
-            Payload
-
-        Returns
-        -------
-        str | None
-            Hashed idempotency key or None
-        """
-        idempotency_key = self._get_hashed_idempotency_key(data=data)
-        if idempotency_key is None:
-            return None
-        return idempotency_key
 
     def _get_hashed_payload(self, data: dict[str, Any]) -> str:
         """
@@ -288,8 +267,10 @@ def save_success(self, data: dict[str, Any], result: dict) -> None:
         result: dict
             The response from function
         """
-        idempotency_key = self._get_idempotency_key_or_return_none(data=data)
+        idempotency_key = self._get_hashed_idempotency_key(data=data)
         if idempotency_key is None:
+            # If the idempotency key is None, no data will be saved in the Persistence Layer.
+            # See: https://github.com/aws-powertools/powertools-lambda-python/issues/2465
             return None
 
         response_data = json.dumps(result, cls=Encoder, sort_keys=True)
@@ -321,8 +302,10 @@ def save_inprogress(self, data: dict[str, Any], remaining_time_in_millis: int |
             If expiry of in-progress invocations is enabled, this will contain the remaining time available in millis
         """
 
-        idempotency_key = self._get_idempotency_key_or_return_none(data=data)
+        idempotency_key = self._get_hashed_idempotency_key(data=data)
         if idempotency_key is None:
+            # If the idempotency key is None, no data will be saved in the Persistence Layer.
+            # See: https://github.com/aws-powertools/powertools-lambda-python/issues/2465
             return None
 
         data_record = DataRecord(
@@ -366,8 +349,10 @@ def delete_record(self, data: dict[str, Any], exception: Exception):
             The exception raised by the function
         """
 
-        idempotency_key = self._get_idempotency_key_or_return_none(data=data)
+        idempotency_key = self._get_hashed_idempotency_key(data=data)
         if idempotency_key is None:
+            # If the idempotency key is None, no data will be saved in the Persistence Layer.
+            # See: https://github.com/aws-powertools/powertools-lambda-python/issues/2465
             return None
 
         data_record = DataRecord(idempotency_key=idempotency_key)
@@ -402,8 +387,10 @@ def get_record(self, data: dict[str, Any]) -> DataRecord | None:
             Payload doesn't match the stored record for the given idempotency key
         """
 
-        idempotency_key = self._get_idempotency_key_or_return_none(data=data)
+        idempotency_key = self._get_hashed_idempotency_key(data=data)
         if idempotency_key is None:
+            # If the idempotency key is None, no data will be saved in the Persistence Layer.
+            # See: https://github.com/aws-powertools/powertools-lambda-python/issues/2465
             return None
 
         cached_record = self._retrieve_from_cache(idempotency_key=idempotency_key)