Remove performance bar from jira connect

What does this MR do and why?

During GitLab for Jira app configuration from a Jira account, the Error: GitLab UI can only be configured once! was thrown for GitLab users with the performance bar enabled (see !149377 (comment 1946926159)):

Console log error

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commons-default-jira_connect_app-pages.admin-pages.admin.application_settings.general-pages.admin.ap-e495bd3c.chunk.js:sourcemap:54885 Uncaught Error: GitLab UI can only be configured once!
    at setConfigs (commons-default-jira_connect_app-pages.admin-pages.admin.application_settings.general-pages.admin.ap-e495bd3c.chunk.js:sourcemap:54885:13)
    at initJiraConnect (jira_connect_app.chunk.js:sourcemap:5658:73)
    at Module.qhnS (jira_connect_app.chunk.js:sourcemap:5687:1)
    at __webpack_require__ (runtime.bundle.js:102:30)
    at checkDeferredModules (runtime.bundle.js:46:23)
    at Array.webpackJsonpCallback [as push] (runtime.bundle.js:33:19)
    at jira_connect_app.chunk.js:sourcemap:1:53
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This change removes the performance bar from the Jira Connect subscriptions view in order to avoid double configuration of the UI.

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