Defect: PassPlanFilePlugin and TagPlugin cannot be used together

[kmanning]

1. Create a pipeline and enable both PassPlanFilePlugin and TagPlugin
2. Run your pipeline, and apply your changes to any environment

Expected: Changes in the plan file should be applied
Actual: Error message:

"Error: Can't set variables when applying a saved plan"

The -var and -var-file options cannot be used when applying a saved plan file,
because a saved plan includes the variable values that were set when it was
created.

Actual command being run: terraform apply -input=false -auto-approve '-var=tags={<tags>}' tfplan-<env>

[kmanning]

Seems like TagPlugin should be enhanced, to allow it to be optionally skipped on apply. Maybe something like...?

TagPlugin.disableOnApply()
                 .init()