Support mixins without vendor pull

[kevcube]

Describe the Feature

I have components that are developed in the same repo as my stacks, I still want to use mixins with them. We would not need to use source or atmos vendor pull

A possible solution is an atmos vendor mixin -c component

Expected Behavior

to be able to update mixins without vendor pull

Use Case

To use mixins without vendor pull-ing any remote files

Describe Ideal Solution

A possible solution is an atmos vendor mixin -c component

Alternatives Considered

No response

Additional Context

No response