feat: update lambda container images and test tool to .NET9

[philasmar]

Issue #, if available:
DOTNET-7790

Description of changes:

• Added .NET9 target for Lambda Container Images and Test Tool
• Dropped .NET7 since it is already out of support
• Updated the CodePipeline to V2 and dropped CodeCommit support
• Updated build script in Lambda Container Images pipeline to create an ECR registry if ones doesn't exist.

Note: The pipelines were deployed to my dev account and ran to completion.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[normj]

We can't drop .NET 6 yet till Lambda actually makes the .NET 6 managed runtime deprecated. Any by deprecated I mean stop allowing customers to create and update .NET 6 Lambda functions. Although there might not be anymore Microsoft patches we might have to patch our code like Amazon.Lambda.RuntimeSupport.

[philasmar]

We can't drop .NET 6 yet till Lambda actually makes the .NET 6 managed runtime deprecated. Any by deprecated I mean stop allowing customers to create and update .NET 6 Lambda functions. Although there might not be anymore Microsoft patches we might have to patch our code like Amazon.Lambda.RuntimeSupport.

Reverted .NET6 changes

[gcbeattyAWS]

code seems fine to me. is there anyway to test the changes before merging? or how were the changes tested?

[normj]

code seems fine to me. is there anyway to test the changes before merging? or how were the changes tested?

I agree with @gcbeattyAWS that a note in the PR description on how this was tested would be good.

[philasmar]

code seems fine to me. is there anyway to test the changes before merging? or how were the changes tested?

I tested the changes by deploying the pipelines to my account and verified that they ran to completion. I also added a note in the description that explains this.