Don't restore launch metadata when --clear-cache

[sclevine]

No description provided.

[ekcasey]

Motivation:

Right now --clear-cache prevents cached layers from being restored. However metadata from the previous image is still provided by the analyzer. This metadata can affect the behavior of the buildpack and result in layers from previous builds being reused rather than rebuilt. Users want to use --clear-cache to achieve a truly clean state. Therefore builds run with --clear-cache should skip the analyzer step.

Acceptance Criteria:

Given I have already built a given image tag once
When I run pack build with the --clear-cache flag
Then in addition to deleting any existing cache image, pack skips the restorer and analyzer lifecycle phases

[mgibson1121]

This story passes acceptance