Pass secrets straight to Lambda like we can with Fargate

### Name of the resource

AWS::Lambda::Function

### Resource name

_No response_

### Description

Just like how in Fargate, a [ContainerDefinition can pass secrets](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-properties-ecs-taskdefinition-containerdefinitions.html#cfn-ecs-taskdefinition-containerdefinition-secrets) straight into environment variables that are otherwise hidden from view, it would be super helpful if Lambda could have the same.

Rather than make a Lambda talk to SecretsManager, and hurting latency, it could just receive secrets by virtue of how it's been configured. If it can work for Fargate, I wonder why it couldn't for Lambda?

### Other Details

_No response_

Start with the AWS::Lambda::Function resource and compare the requested behavior with the linked Fargate ContainerDefinition secrets support and AWS Secrets Manager. Define the supported configuration and its security and latency behavior; done means the Lambda resource can pass configured secrets into environment variables without requiring application-side retrieval.

Written by the indexing model from the issue text.