Support for standardized service endpoint

[aklakina]

Disclaimer

I know there are lot of pull requests and issues trying to cover this issue but I didn't find any that is generic enough to be useable by any and all service endpoint integration.

Description

This pull request introduces comprehensive support for managing and retrieving Service Endpoints through Terraform in a standardized manner.

The following key changes are included:

1. New Resource: azuredevops_serviceendpoint_generic_v2

• Purpose:
  Enables users to create and manage Service Endpoints in Azure DevOps, supporting integration with external services using custom authentication mechanisms.
• Features:
  • Directly integrates with how Azure Devops manages service endpoints
  • Has minimal amount of required attributes, everything else is gathered from Azure Devops through api.
  • The configuration is validated during plan time to evaluate what data is missing or not appropriate.
• Documentation:
  • Provides detailed usage examples for different authentication types.
  • Lists all supported arguments and exported attributes.
  • Includes import instructions for existing service endpoints.

2. New Data Source: azuredevops_serviceendpoint_generic_v2

• Purpose:
  Allows users to retrieve information about existing Service Endpoints by either ID or name, facilitating data-driven Terraform configurations.
• Features:
  • Supports lookup by both service_endpoint_id and service_endpoint_name.
  • Exposes all relevant attributes, including authorization details and custom data.
• Documentation:
  • Offers example queries for both lookup methods.
  • Clearly documents all arguments and exported attributes.

3. Documentation

• Resource Documentation:
  • Located in website/docs/r/serviceendpoint_generic_v2.html.markdown.
  • Explains resource arguments, attributes, and provides multiple usage scenarios.
• Data Source Documentation:
  • Located in website/docs/d/serviceendpoint_generic_v2.html.markdown.
  • Details data source arguments, attributes, and example queries.

4. Benefits

Standardized:

No need for specific service endpoint resource or data besides this.

---

These enhancements significantly improve the Azure DevOps Terraform provider by enabling any service endpoint scenario without the need for adding a new service endpoint integration.

All Submissions:

• Have you added an explanation of what your changes do and why you'd like us to include them?
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.
• My code follows the code style of this project.
• I ran lint checks locally prior to submission.
• Have you checked to ensure there aren't other open PRs for the same update/change?

What about the current behavior has changed?

Issue Number:

• Rapid7 service endpoint #219
• Add Service Endpoint for Custom Services #628
• Custom service endpoint support #683
• Add azuredevops_serviceendpoint_aws_terraform resource #767
• Added support for data_serviceendpoint_kubernetes #926
• Add new resource for aqua platform service connection/ednpoint #1367
• Data Source - azuredevops_serviceendpoint_jfrog_[*]_v2 - Missing #1231 and Feature: Add JFrog V2 Service Endpoint Data Source (Issue #1231) #1232
• azuredevops_serviceendpoint_azurerm / remove subscription scope dependency #1385
• GCP Terraform Service Connection error - 'the string provided in credentials is neither valid json nor a valid file path' #1376

Does this introduce a change to go.mod, go.sum or vendor/?

• Yes
• No

Does this introduce a breaking change?

• Yes
• No