feat: Add ephemeral_storage_size variable

[carterjones]

Description

When using this module in GovCloud, we get this error (this is sanitized):

│ Error: error modifying Lambda Function (lambda-name) configuration : InvalidParameterValueException: Ephemeral storage configuration ('ephemeralStorage') is currently not supported. Please remove the ephemeral storage parameter from your request and try again.
│ {
│   RespMetadata: {
│     StatusCode: 400,
│     RequestID: "..."
│   },
│   Message_: "Ephemeral storage configuration ('ephemeralStorage') is currently not supported. Please remove the ephemeral storage parameter from your request and try again.",
│   Type: "User"
│ }

This was fixed in 3.1.1 of terraform-aws-lambda: terraform-aws-modules/terraform-aws-lambda#304 (comment)

This PR does two things:

1. Upgrades the version of terraform-aws-lambda to the latest: 3.2.0
2. Allows for the configuration of ephemeral_storage_size by adding a new variable.

When adding the new variable, I followed the naming scheme I observed here (e.g.: lambda_function_variable_name_from_submodule):

terraform-aws-notify-slack/variables.tf

Lines 135 to 163 in 1d7bfe9

	variable "lambda_function_tags" {
	description = "Additional tags for the Lambda function"
	type = map(string)
	default = {}
	}
	variable "lambda_function_vpc_subnet_ids" {
	description = "List of subnet ids when Lambda Function should run in the VPC. Usually private or intra subnets."
	type = list(string)
	default = null
	}
	variable "lambda_function_vpc_security_group_ids" {
	description = "List of security group ids when Lambda Function should run in the VPC."
	type = list(string)
	default = null
	}
	variable "lambda_function_store_on_s3" {
	description = "Whether to store produced artifacts on S3 or locally."
	type = bool
	default = false
	}
	variable "lambda_function_s3_bucket" {
	description = "S3 bucket to store artifacts"
	type = string
	default = null
	}

I copied the description, type, and default from here: https://github.com/terraform-aws-modules/terraform-aws-lambda/blob/19b9f11fc8ed04a34c02db553d3f463cab6b740a/variables.tf#L112-L116

Motivation and Context

Without this change, using this module in GovCloud results in this error:

Ephemeral storage configuration ('ephemeralStorage') is currently not supported. Please remove the ephemeral storage parameter from your request and try again.

This is the same issue described here: terraform-aws-modules/terraform-aws-lambda#304

Breaking Changes

This does not break backward compatibility. The default in this module (512) is the same as the default used by the terraform-aws-lambda module (512).

How Has This Been Tested?

• I have executed pre-commit run -a on my pull request
• I tested this by running terraform apply with it in GovCloud. The error no longer occurs when I set lambda_function_ephemeral_storage_size to null.

[antonbabenko]

Thank you, @carterjones !

[antonbabenko]

This PR is included in version 5.1.0 🎉

[github-actions]

I'm going to lock this pull request because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active issues. If you have found a problem that seems related to this change, please open a new issue and complete the issue template so we can capture all the details necessary to investigate further.