Sync GitLab linked issue back to Sentry on SentryIssue creation

What does this MR do?

When an issue is created in GitLab based on a Sentry error, this MR adds logic to POST to Sentry with the reciprocal link. So when a user sees the error in Sentry, they will see the link to the GitLab issue as well.

Also fixes a recently introduced FE bug that blocks this functionality. (sentryId)

Related Issue: #37307 (closed)

Pre-requisite MR: !23015 (merged)

Screenshots

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

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