Issue Summary

Connect on Forge apps, with Global or Project Permissions, when migrating it to a pure Forge module, following: Jira Global Permission module and Jira Project Permission module causes existing permissions to have the default assigned groups in the defaultGrants property to be added, as noted in the documentation of the Forge module, as well as in the Connect module, it should happen:

Please note that the existing permission configuration won't be overwritten during add-on upgrades or re-installations. 

Steps to Reproduce

1. Create a Connect app, and add a simple global permission module to it, and have the defaultGrants set to all
2. Install the app, check the permissions, and remove some groups from it.
3. Migrate the Connect app to Forge
4. Install the Forge app. Note that the groups assigned to the custom permission won't change (as expected).
5. Follow the instructions and migrate the Connect Module to a Pure Forge module.
6. Deploy the app
7. Check the permission; all groups were re-assigned to it.

Expected Results

Existing permissions shouldn't be modified when migrating the Connect Module to a Pure Forge module in the app's manifest file.

Actual Results

When you deploy the app after migrating the module, it reassigns all the groups to the permission. 

Workaround

You can migrate it to Forge using None in the defaultGrants, but it's not always feasible because it will serve only existing customers; new ones will not have any user group assigned to the custom permission, and this is not always the expected feature when you develop an app using those permission modules.