Atlassian has changed API endpoint for fetching tickets

[cemtopkaya]

Summary

This pull request updates the Jira API integration in the extension to comply with the latest Atlassian Cloud changes. The previous implementation relied on GET /rest/api/latest/search?jql=..., which has been removed by Atlassian (see [changelog](https://developer.atlassian.com/changelog/#CHANGE-2046)).

The new API requires using POST /rest/api/3/search/jql with the JQL query provided in the request body.

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Changes

• Replaced axios.get(CONSTANTS.url(baseUrl), …) with a POST request to ${baseUrl}/rest/api/3/search/jql.
• Moved the JQL query and maxResults into the request body, as required by the new endpoint.
• Added explicit request headers (Accept and Content-Type) to align with Atlassian’s API specification.
• Limited returned fields to key, summary, and updated to reduce payload size.

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Motivation

Without this change, the extension fails to fetch issues from Jira Cloud because the old endpoint returns:

{
  "errorMessages": [
    "The requested API has been removed. Please migrate to the /rest/api/3/search/jql API."
  ],
  "errors": {}
}

This update restores compatibility with Jira Cloud instances and ensures that users can continue fetching their assigned tickets.

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Testing

• Verified against a Jira Cloud instance (atlassian.net) using API tokens.
• Confirmed that issues are returned and mapped correctly into the extension’s quick pick list.

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Notes

• This change only affects Jira Cloud users. Jira Server/DC users (who still support GET /rest/api/2/search) may require separate handling if backward compatibility is a concern.
• Documentation updates may be needed to reflect the new API usage.