apigw-lambda-dynamodb-terraform: Update runtime to python3.12

[kakakakakku]

Issue #, if available:
N/A

Description of changes:
Hi😀 Thanks for the useful patterns!

I updated the Lambda Python runtime version to python3.12.

While testing apigw-lambda-dynamodb-terraform, I noticed that the Lambda runtime version python3.8 was deprecated. Although it's still deployable at the moment, it will not be allowed after October 1, 2025.
https://docs.aws.amazon.com/lambda/latest/dg/lambda-runtimes.html

To prevent future deployment issues, I updated the runtime to python3.12.
https://github.com/terraform-aws-modules/terraform-aws-lambda

Check

terraform apply completed successfully and works good.

$ curl -X POST ${apigwy_url}/movies
{"message": "Successfully inserted data!"}%

$ curl -X POST ${apigwy_url}/movies \
    --header 'Content-Type: application/json' \
    -d '{"year":1977, "title":"Starwars"}' 
{"message": "Successfully inserted data!"}%

Thank you😀

---

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[kakakakakku]

note: Older version does not support Python 3.12 runtime. So I updated the version to v5.

[kakakakakku]

note: The following error occurred when applying.

╷
│ Error: creating S3 Bucket (apigw-lambda-ddb20250719083122545300000001) ACL: operation error S3: PutBucketAcl, https response error StatusCode: 400, RequestID: RTCDVY9T5Y9NE0MW, HostID: vfd4QSf6vdz0D13xfdcM0lQDDIncDGdaEDF5Zsu1HhwOzmpYDt5r3C/0j1MKxlXp2QAnWBExjFw=, api error AccessControlListNotSupported: The bucket does not allow ACLs
│ 
│   with aws_s3_bucket_acl.private_bucket,
│   on main.tf line 58, in resource "aws_s3_bucket_acl" "private_bucket":
│   58: resource "aws_s3_bucket_acl" "private_bucket" {
│ 
╵

This issue is related to the changes described in the following blog post. To fix this, I enabled Block Public Access for the S3 bucket😀

Disabling ACLs is an S3 security best practice, and in April of 2023, we disabled ACLs by default for all new buckets.
https://aws.amazon.com/jp/blogs/storage/disabling-acls-for-existing-amazon-s3-workloads-with-information-in-s3-server-access-logs-and-aws-cloudtrail/