B2CA-1648: Port Flex

[cedelavergne-ledger]

Port App to Flex.

This includes:

• Port NBGLv2
• Adapt tests using scenario_navigator
• Update version

Checklist

• App update process has been followed
• Target branch is develop
• Application version has been bumped

[tdejoigny-ledger]

a small change is required in codeql CI (add Flex target)

this line:
sdk: ["$NANOS_SDK", "$NANOX_SDK", "$NANOSP_SDK", "$STAX_SDK"]

[tdejoigny-ledger]

and same as for Tron it seems that the swap tests are not running for Flex target.
cc: @fbeutin-ledger

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