Move some scripts to framework submodule

[davidhorstmann-arm]

Move code_style.py and test code generation scripts to the framework submodule.

Depends on Mbed-TLS/mbedtls-framework#5

Note: The framework submodule is updated to the tip of Mbed-TLS/mbedtls-framework#5 to get the CI results. I can rebase this once that PR is merged.

PR checklist

Please tick as appropriate and edit the reasons (e.g.: "backport: not needed because this is a new feature")

• [x] changelog not required - internal change only
• [x] 3.6 backport #9012
• [x] 2.28 backport not required - framework is 3.x only
• [x] tests not required file moves only

[davidhorstmann-arm]

[Force-pushed to update to version of submodule with full history]

[davidhorstmann-arm]

Thanks for catching these, should be addressed now!

[davidhorstmann-arm]

Closing as superseded by more separate PRs