Change admin bar notifications URL

[igorschoester]

Context

• Pointing the admin bar notifications link to the alert center instead of the default route (dashboard)

Summary

This PR can be summarized in the following changelog entry:

• Changes the admin bar notification URL to point to the alert center.
• Changes the Dashboard' learn more link copy and URL.

Relevant technical choices:

Test instructions

Test instructions for the acceptance test before the PR gets merged

This PR can be acceptance tested by following these steps:

Alert center link

• Ensure you have the admin bar enabled and see Yoast SEO in there
• Click on the Yoast icon
  
• Verify you went to the Dashboard page: admin.php?page=wpseo_dashboard
• Hover over the Yoast icon and click on the Notifications
  
• Verify you went to the Alert center page: admin.php?page=wpseo_dashboard#/alert-center

There is a check for permissions (can manage options), but since it is the same for even having the page I have no clue how to even test that.

Dashboard copy

• Go to the dashboard
• Verify the link in the description now has the copy: Learn more about the dashboard
• Verify the link is https://yoa.st/dashboard-learn-more

Relevant test scenarios

• Changes should be tested with the browser console open
• Changes should be tested on different posts/pages/taxonomies/custom post types/custom taxonomies
• Changes should be tested on different editors (Default Block/Gutenberg/Classic/Elementor/other)
• Changes should be tested on different browsers
• Changes should be tested on multisite

Test instructions for QA when the code is in the RC

• QA should use the same steps as above.

QA can test this PR by following these steps:

Impact check

This PR affects the following parts of the plugin, which may require extra testing:

UI changes

• This PR changes the UI in the plugin. I have added the 'UI change' label to this PR.

Other environments

• This PR also affects Shopify. I have added a changelog entry starting with [shopify-seo], added test instructions for Shopify and attached the Shopify label to this PR.

Documentation

• I have written documentation for this change. For example, comments in the Relevant technical choices, comments in the code, documentation on Confluence / shared Google Drive / Yoast developer portal, or other.

Quality assurance

• I have tested this code to the best of my abilities.
• During testing, I had activated all plugins that Yoast SEO provides integrations for.
• I have added unit tests to verify the code works as intended.
• If any part of the code is behind a feature flag, my test instructions also cover cases where the feature flag is switched off.
• I have written this PR in accordance with my team's definition of done.
• I have checked that the base branch is correctly set.

Innovation

• No innovation project is applicable for this PR.
• This PR falls under an innovation project. I have attached the innovation label.
• I have added my hours to the WBSO document.

Fixes https://github.com/Yoast/reserved-tasks/issues/351
Fixes https://github.com/Yoast/reserved-tasks/issues/352

[thijsoo]

CR + ACC 👍

[hardikgohil7988]

Verified yoast icon and notification in admin bar on dashbaord and alert center pages
Verified learn more link and redirection on dashboard