[Module Proposal]: `avm/utl/general/get-environment`

### Check for previous/existing GitHub issues/module proposals

- [X] I have checked for previous/existing GitHub issues/module proposals.

### Check this module doesn't already exist in the module indexes

- [X] I have checked for that this module doesn't already exist in the module indexes; or I'm proposing the module to be migrated from CARML/TFVM.

### Bicep or Terraform?

Bicep

### Module Classification?

Pattern Module

### Module Name

avm/utl/general/get-environment

### Module Details

The goal is to put something in the registry that solves this issue:
https://github.com/Azure/bicep/issues/12482

In the style described by @anthony-c-martin in this comment:
https://github.com/Azure/bicep/issues/12482#issuecomment-2030675534

### Do you want to be the owner of this module?

Yes

### Module Owner's GitHub Username (handle)

alex-frankel

### (Optional) Secondary Module Owner's GitHub Username (handle)

emilyredm