Fix documentation on the scope of PAT for GitLab plugin for JetBrains IDE
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### Summary
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We mention using the PAT scope `ai_features` [here](https://docs.gitlab.com/ee/user/profile/personal_access_tokens.html#personal-access-token-scopes) to address a JetBrains security vulnerability, but starting from [this](https://gitlab.com/gitlab-org/editor-extensions/gitlab-jetbrains-plugin/-/merge_requests/313/diffs#8ec9a00bfd09b3190ac6b22251dbb1aa95a0579d_43_40) MR, we updated the configuration steps to use the `api` scope of PAT and this was subsequently ported over to the [documentation](https://docs.gitlab.com/ee/editor_extensions/jetbrains_ide/setup.html#create-a-personal-access-token).
It was noted from a test 5 months ago that there were some issues with using the PAT scope `ai_features`: https://gitlab.com/gitlab-org/editor-extensions/gitlab-jetbrains-plugin/-/merge_requests/447#note_1958848396. We may need to make some tests to confirm if there are still issues before updating the documentation back to `ai_features` scope for JetBrains IDE.
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