CI: Port ec2_compatibilitytests

[willieyz]

• Resolves: CI: Port ec2_compatibilitytests #583

• This PR ports ec2_compatibilitytests to mldsa-native, referencing the implementation from mlkem-native.

• This PR includes the following changes:

  • Add ec2_compatibilitytests to ci.yml.
  • Since ec2_compatibilitytests requires ci_ec2_container.yml, this PR constructs and adds ci_ec2_container.yml based on ci_ec2_reuseable.yml, referencing from mlkem-native.

• Comparison between ci_ec2_reuseable.yml and ci_ec2_container.yml:

  • ci_ec2_container.yml modifies the ec2_volume_size and removes the input: ec2_volume_size.
  • ci_ec2_container.yml does not include the following inputs: test, config_variation.
  • Adds an additional input: container in ci_ec2_container.yml for testing with different container images.
  • Adds Manual checkout steps, with same reason in mlkem-native.
  • Both use same subnet-id, security-group-id and AMI env

[willieyz]

Hi @hanno-becker , sorry to bother you,
I’m currently working on porting the ec2_compatibilitytests to mldsa-native, and I noticed that the workflow for mlkem-native uses a custom AMI.
Could you please share how that AMI was created or configured for mlkem-native?
We plan to set up a new EC2 instance with the same environment to ensure consistency for mldsa-native testing.
Thank you for your time and support!