Fixed Microsoft Teams notifications

[marcusmoore]

Description

We currently have two ways to send webhooks to Microsoft Teams since one is being deprecated in the near future. This PR fixes a bug where we were accidentally not checking for which version should be used in the listener.

It also fixes a bug where the integrations page was not rendering.

Note: We don't have an old webhook to test with so we're going on prayers that the old version still works.

Type of change

• Bug fix (non-breaking change which fixes an issue)

[what-the-diff]

PR Summary

• Refinement of Code Structure
  The CheckoutableListener.php file now incorporates a Str use statement for a more streamlined and efficient operation.

• Improved Webhook Selection Process
  Optimization of Microsoft Teams webhook selection has been carried out. This includes replacing the old setting check with a new dedicated method - newMicrosoftTeamsWebhookEnabled(). This development was introduced for enhancing the readability of the code and making the content more manageable.

• New Method Introduction
  The method newMicrosoftTeamsWebhookEnabled() was introduced to the CheckoutableListener.php file. This method takes over the responsibility of Microsoft Teams' webhook checks by analyzing the presence of 'workflows' in the webhook endpoint.

• Change in Return Type Declaration
  The return type declaration of the toMicrosoftTeams() method within the CheckoutAssetNotification.php underwent alterations. It no longer contains hinting with an array, which suggests changes to the expected return format, potentially indicating increased flexibility or broader application.