feat: Adds mongodbatlas_project_ip_addresses data source

[rubenVB01]

Description

In this PR I implement the new mongodbatlas_project_ip_addresses Data Source. This PR includes the implementation, testing and documentation. As a follow-up, there will also be a deprecation for the ip_addresses attribute in the project resource and data source.

Link to any related issue(s): CLOUDP-262915

Agustin Edit:
Using the following configuration

data "mongodbatlas_project_ip_addresses" "with-cluster" {
  project_id = var.project_id
}

Verified all possible scenarios:

• no clusters
• cluster being created which returns a cluster element with empty ip addresses
• cluster after creation which defined inbound and outbound ip addresses

Type of change:

• Bug fix (non-breaking change which fixes an issue). Please, add the "bug" label to the PR.
• New feature (non-breaking change which adds functionality). Please, add the "enhancement" label to the PR. A migration guide must be created or updated if the new feature will go in a major version.
• Breaking change (fix or feature that would cause existing functionality to not work as expected). Please, add the "breaking change" label to the PR. A migration guide must be created or updated.
• This change requires a documentation update
• Documentation fix/enhancement

Required Checklist:

• I have signed the MongoDB CLA
• I have read the contributing guides
• I have checked that this change does not generate any credentials and that they are NOT accidentally logged anywhere.
• I have added tests that prove my fix is effective or that my feature works per HashiCorp requirements
• I have added any necessary documentation (if appropriate)
• I have run make fmt and formatted my code
• If changes include deprecations or removals I have added appropriate changelog entries.
• If changes include removal or addition of 3rd party GitHub actions, I updated our internal document. Reach out to the APIx Integration slack channel to get access to the internal document.

Further comments

[oarbusi]

Good work, some things to take into account:

• Tests should be included in this PR and ideally make the test run in the CI, if not, we can't be 100% sure that what is being merged to master is working as we expect.
• when a feat PR is created, a changelog entry must be included in the PR, check this guide
• PR title does not need to include Cloudp 262915, you could change it to "feat: Adds mongodbatlas_project_ip_addresses data source"

[oarbusi]

could we have a test where a cluster is created in the project and it has some inbound and outbound ip addresses?

[AgustinBettati]

have my doubts if we want to include a cluster creation/deletion for this, considering we do have a unit test that verifies correct handling of a complete response with ip addresses. No strong opinion, looping in @lantoli @maastha @EspenAlbert @marcosuma in case there is additional inputs.

[AgustinBettati]

some additional points to consider

[EspenAlbert]

LGTM

[lantoli]

@AgustinBettati knit: this seems like a singular ds, i see API endpoint is in plural, but wonder if we should call this ds mongodbatlas_project_ip_address.

as an example this ds doesn't seem to have the normal attributes of a plural ds such as results

[AgustinBettati]

Good call out.
Definitely not our regular case of plural data source with results. I was taking inspiration from mongodbatlas_control_plane_ip_addresses that is similar in the sense that is it an isolated data source associated to single get endpoint, and API is not using regular pagination to return all results. As both of them return multiple ip addresses thought this name would be more appropriate.