Allow iteration ids to be passed as a Global ID

What does this MR do?

For query such as

query issue_iteration {
  project(fullPath: "h5bp/html5-boilerplate") {
    name
    issues(iterationId: "gid://gitlab/Iteration/1") {
      edges {
        node {
          id
          iid
          title
          iteration {
            title
            id
            iid
          }
        }
      }
    }
  }
}

only a raw id could be passed in as iterationId. Added support for using a GlobalID

Screenshots (strongly suggested)

Does this MR meet the acceptance criteria?

Conformity

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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
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Security

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Related to #284011 (closed)