Ability to re-use Shots for different Entities

Description

When importing a cut against a specific Entity (a Sequence, an Episode, etc...) Shots linked to the Projects are now used if matching Shots can't be found for the target Entity, allowing Shots to be re-used for different contexts.
Before, only Shots linked to the target Entity were considered.

What's Changed

• For #15193, Shot re-use by @gplsteph in #61

Full Changelog: 1.1.7...1.1.8