Preserve the powerstate after modifing EC2 attr which requires stop

[8me]

Rollback Plan

If a change needs to be reverted, we will publish an updated version of the library.

Description

When one of the attributes is changed which require a start/stop, the EC2 is powered on even if it was in powerstate on before. This one is a sketch to introduce a flag which allows to skip the start if it was off.
With the flag, the change should not cause a breaking change to the behavior of the provider.

Testing

Did not add some tests for now, as I would need some help to properly implement this.

Cannot run acceptance test as EC2 type changes are not included in free tier AWS.

[github-actions]

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