docs: docstrings to signal v1/v2

Author: heitorlessa

Diff for: aws_lambda_powertools/event_handler/api_gateway.py

@@ -743,6 +743,7 @@ def __init__(
         serializer: Optional[Callable[[Dict], str]] = None,
         strip_prefixes: Optional[List[str]] = None,
     ):
+        """Amazon API Gateway REST and HTTP API v1 payload resolver"""
         super().__init__(ProxyEventType.APIGatewayProxyEvent, cors, debug, serializer, strip_prefixes)
 
 
@@ -756,6 +757,7 @@ def __init__(
         serializer: Optional[Callable[[Dict], str]] = None,
         strip_prefixes: Optional[List[str]] = None,
     ):
+        """Amazon API Gateway HTTP API v2 payload resolver"""
         super().__init__(ProxyEventType.APIGatewayProxyEventV2, cors, debug, serializer, strip_prefixes)
 
 
@@ -769,4 +771,5 @@ def __init__(
         serializer: Optional[Callable[[Dict], str]] = None,
         strip_prefixes: Optional[List[str]] = None,
     ):
+        """Amazon Application Load Balancer (ALB) resolver"""
         super().__init__(ProxyEventType.ALBEvent, cors, debug, serializer, strip_prefixes)