Optimize Metadata fetch

[jonesbusy]

Optimize Metadata fetch by skiping fork, sync, compile and verification in this mode activated when only the fetch recipe is activated

Fix #207

Testing done

Automated tests and check logs on runtime

Skipping push changes for plugin asm-api in fetch-metadata-only mode
Skipping pull request for plugin asm-api in fetch-metadata-only mode
No changes to commit for plugin asm-api
Skipping push changes for plugin asm-api in fetch-metadata-only mode
Skipping pull request for plugin asm-api in fetch-metadata-only mode
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Plugin: asm-api
Metadata was fetched for plugin asm-api and is available at ~/.cache/jenkins-plugin-modernizer-cli/asm-api/plugin-metadata
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Submitter checklist

• Make sure you are opening from a topic/feature/bugfix branch (right side) and not your main branch!
• Ensure that the pull request title represents the desired changelog entry
• Please describe what you did
• Link to relevant issues in GitHub or Jira
• Link to relevant pull requests, esp. upstream and downstream changes
• Ensure you have provided tests - that demonstrates feature works or fixes the issue

[gounthar]

Exactly what I needed, thank you! 🤗