Fix typo with `var.resource_group_creation_enabled`

[jtracey93]

Description

This pull request addresses a typo in the variable name resoruce_group_creation_enabled by correcting it to resource_group_creation_enabled across multiple files. This change ensures consistency and prevents potential issues related to the misspelled variable.

closes #32

Key changes include:

Documentation Updates:

• README.md: Corrected the typo in the variable name from resoruce_group_creation_enabled to resource_group_creation_enabled.

Example Configuration Updates:

• examples/with-vnet-link-existing-rg/README.md: Updated the example configuration to use the corrected variable name.
• examples/with-vnet-link-existing-rg/main.tf: Updated the example configuration to use the corrected variable name.

Main Configuration Updates:

• main.tf: Corrected the variable name in multiple instances to ensure the correct variable is referenced throughout the main configuration. [1] [2] [3]
• outputs.tf: Updated the output to reference the corrected variable name.
• variables.tf: Corrected the variable definition to ensure the correct variable name is used.

Type of Change

• [ ] Non-module change (e.g. CI/CD, documentation, etc.)
• [x] Azure Verified Module updates:
  • [ ] Bugfix containing backwards compatible bug fixes
  • [x] Someone has opened a bug report issue, and I have included "Closes #{bug_report_issue_number}" in the PR description.
  • [ ] The bug was found by the module author, and no one has opened an issue to report it yet.
  • [ ] Feature update backwards compatible feature updates.
  • [x] Breaking changes.
  • [ ] Update to documentation

Checklist

• [x] I'm sure there are no other open Pull Requests for the same update/change
• [x] My corresponding pipelines / checks run clean and green without any errors or warnings
• [x] I did run all pre-commit checks