Exclude dev and test deps from docker images

[seanstory]

Part of #430

Looks like we're not correctly stripping out our dev/test dependencies at build time.

After merging this, we probably need to cut a new release.

Checklists

Pre-Review Checklist

• This PR does NOT contain credentials of any kind, such as API keys or username/passwords (double check crawler.yml.example and elasticsearch.yml.example)
• This PR has a meaningful title
• This PR links to all relevant GitHub issues that it fixes or partially addresses
  • If there is no GitHub issue, please create it. Each PR should have a link to an issue
• this PR has a thorough description
• Covered the changes with automated tests
• Tested the changes locally
• Added a label for each target release version (example: v0.1.0)
• Considered corresponding documentation changes
• Contributed any configuration settings changes to the configuration reference
• Ran make notice if any dependencies have been added

Release Note

Fixes a packaging bug that was causing CVE scanners to flag false positives on Open Crawler

[seanstory]

@mattnowzari can you take a look?

[artem-shelkovnikov]

How's the image size difference after this change?

[seanstory]

50MB → 339MB — a 111MB reduction (~25%) on the production wolfi image just by excluding dev/test gems