updating go-azure-helpers to v0.22.0 / updating usages of identity

[tombuildsstuff]

This PR includes:

1. dependencies: upgrading github.com/hashicorp/go-azure-helpers to v0.22.0
2. handling the breaking changes in that upgrade
3. refactors existing identity blocks to using the new common schema
4. also refactors identity within the storage account - this is currently Optional & Computed but the Computed value isn't used, so can just be Optional.
5. synapse workspace, identity becomes required in 3.0 - this is currently defaulted in the create and so computed, but in line with Consistent Identity Blocks across the provider #15187 should be required

[manicminer]

Just some minor import ordering but otherwise LGTM 🚀

[github-actions]

This functionality has been released in v2.95.0 of the Terraform Provider. Please see the Terraform documentation on provider versioning or reach out if you need any assistance upgrading.

For further feature requests or bug reports with this functionality, please create a new GitHub issue following the template. Thank you!

[github-actions]

I'm going to lock this pull request because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active contributions.
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