Social: Change Manage connections button to a link with connections

[gmjuhasz]

Fixes https://github.com/Automattic/jetpack-reach/issues/442

Proposed changes:

• Eder suggested that we only use buttons for main actions, so the manage connection button is changed back to link if the number of connections is greater than 0.

Other information:

• Have you written new tests for your changes, if applicable?
• Have you checked the E2E test CI results, and verified that your changes do not break them?
• Have you tested your changes on WordPress.com, if applicable (if so, you'll see a generated comment below with a script to run)?

Jetpack product discussion

https://github.com/Automattic/jetpack-reach/issues/442

Does this pull request change what data or activity we track or use?

No.

Testing instructions:

• Go to the editor, and validate the states.
• You can mimic having no connections by returning [] in with getConnections in projects/js-packages/publicize-components/src/social-store/selectors/connection-data.js
• The link and button should have the same functionality which is opening the connections modal

No connections	Having connections

[github-actions]

Are you an Automattician? Please test your changes on all WordPress.com environments to help mitigate accidental explosions.

• To test on WoA, go to the Plugins menu on a WordPress.com Simple site. Click on the "Upload" button and follow the upgrade flow to be able to upload, install, and activate the Jetpack Beta plugin. Once the plugin is active, go to Jetpack > Jetpack Beta, select your plugin, and enable the change/social-manage-connection-link branch.

• To test on Simple, run the following command on your sandbox:

  bin/jetpack-downloader test jetpack change/social-manage-connection-link
  

Interested in more tips and information?

• In your local development environment, use the jetpack rsync command to sync your changes to a WoA dev blog.
• Read more about our development workflow here: PCYsg-eg0-p2
• Figure out when your changes will be shipped to customers here: PCYsg-eg5-p2

[github-actions]

Thank you for your PR!

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[manzoorwanijk]

Works well