Migrate from Terraform Plugin SDKv2 to new Provider Framework

[jimeh]

Terraform's Plugin SDK was recently superseded by the Plugin Framework:

• https://developer.hashicorp.com/terraform/plugin/framework
• https://github.com/hashicorp/terraform-plugin-framework

Providers can be slowly migrated piece by piece over to the new framework, by hosting both protocol v5 (SDKv2) and v6 (Framework) providers within the same one provider binary:

• https://developer.hashicorp.com/terraform/plugin/mux/translating-protocol-version-5-to-6

- [ ] #107
- [ ] #108
- [ ] https://github.com/krystal/terraform-provider-katapult/issues/111
- [ ] https://github.com/krystal/terraform-provider-katapult/issues/120
- [ ] https://github.com/krystal/terraform-provider-katapult/issues/121
- [ ] https://github.com/krystal/terraform-provider-katapult/issues/123

Progress

• [ ] Setup plugin framework
• [ ] Migrate Resources to Framework:
  • [x] katapult_ip
  • [ ] katapult_security_group
  • [ ] katapult_security_group_rule
  • [ ] katapult_virtual_machine
  • [ ] katapult_virtual_machine_group
• [ ] Migrate Data Sources to Framework:
  • [ ] katapult_data_center
  • [ ] katapult_disk_template
  • [ ] katapult_disk_templates
  • [x] katapult_ip
  • [ ] katapult_network_speed_profile
  • [ ] katapult_network_speed_profiles
  • [ ] katapult_security_group
  • [ ] katapult_security_group_rule
  • [ ] katapult_security_group_rules
  • [ ] katapult_security_groups
  • [ ] katapult_virtual_machine
  • [ ] katapult_virtual_machine_group
  • [ ] katapult_virtual_machine_groups
  • [ ] katapult_virtual_machine_package
  • [ ] katapult_virtual_machine_packages
• [ ] Use Framework for any new Resources and Data Sources.