Rename userPoolGroups folder

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**Is your feature request related to a problem? Please describe.**
We cannot follow a naming convention for our project. userPoolGroups and AdminQueries, these folders are created by amplify. Two of them are in different naming convention.

**Describe the solution you'd like**
We want to be consistent in case our project's naming convention. We want to make folder with Pascal case. We can do it if we have got the chance to name userPoolGroups by ourselves.
**Describe alternatives you've considered**
A clear and concise description of any alternative solutions or features you've considered.

**Additional context**
Add any other context or screenshots about the feature request here.