Add ability to resume when downloaded database is available

[mikeybinns]

Fixes #575

Testing steps:

1. Pull down branch
2. Run commands via npx npx <Absolute path to project>/packages/packages/cli pull-database
3. Change DB_HOST to "" in wp-config to force failure in the import stage.
4. Run import, it'll download DB and fail
5. Fix wp-config, then run command again with the following results:
   • If --resume flag used, it will import using the existing file, no prompt
   • If --fresh flag is used, it will delete the existing file, download a new one and import, no prompt
   • If no flag is used, get a prompt asking whether you want to use the file or not
   • If you select "Resume from existing file (timestamp)", it'll use the existing file
   • If you select "Start new download" it will delete the existing file, download a new one and import
   • If you use both --resume and --fresh flags at once, it will throw an error.

[changeset-bot]

🦋 Changeset detected

Latest commit: 38ded5d

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@atomicsmash/cli	Minor

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