Added a check on provider's configuration for required env vars

[duedares-rvj]

🔧 Changes

Added ConfigureContextFunc which checks if AUTH0_DOMAIN, AUTH0_CLIENT_ID and AUTH0_CLIENT_SECRET are configured before planning.

📚 References

Addressed https://github.com/auth0/terraform-provider-auth0/issues/1023

🔬 Testing

📝 Checklist

• [ ] All new/changed/fixed functionality is covered by tests (or N/A)
• [ ] I have added documentation for all new/changed functionality (or N/A)

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 0% with 18 lines in your changes missing coverage. Please review.

Project coverage is 89.27%. Comparing base (98823c3) to head (d6ca71a).

Files with missing lines	Patch %	Lines
internal/provider/provider.go	0.00%	17 Missing and 1 partial :warning:

Additional details and impacted files

[](https://app.codecov.io/gh/auth0/terraform-provider-auth0/pull/1053?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=auth0) ```diff @@ Coverage Diff @@ ## main #1053 +/- ## ========================================== - Coverage 89.37% 89.27% -0.10% ========================================== Files 126 126 Lines 17471 17487 +16 ========================================== - Hits 15614 15612 -2 - Misses 1318 1335 +17 - Partials 539 540 +1 ``` | [Files with missing lines](https://app.codecov.io/gh/auth0/terraform-provider-auth0/pull/1053?dropdown=coverage&src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=auth0) | Coverage Δ | | |---|---|---| | [internal/provider/provider.go](https://app.codecov.io/gh/auth0/terraform-provider-auth0/pull/1053?src=pr&el=tree&filepath=internal%2Fprovider%2Fprovider.go&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=auth0#diff-aW50ZXJuYWwvcHJvdmlkZXIvcHJvdmlkZXIuZ28=) | `75.67% <0.00%> (-24.33%)` | :arrow_down: |