Create issue from alert

What does this MR do?

Adds the ability to create issue from alert and view related issue when it exists already

🇺🇦 Functionality is behind the feature flag alert_management_create_alert_issue

Screenshots

Create issue

Fixed loader on Create issue button

Old create issue button (with loader issue) for comparison

Error on issue creation

View issue when it exists

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers
• Informed Infrastructure department of a default or new setting change, if applicable per definition of done

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• Label as security and @ mention @gitlab-com/gl-security/appsec
• The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• Security reports checked/validated by a reviewer from the AppSec team

References #217745 (closed)