RUMM-1582 Fix DDRUMView and DDRUMAction APIs for Objective-C

[ncreated]

What and why?

🐞 As noticed in #577 (comment), DDRUMView and DDRUMAction were not properly exposed to Objective-C interface.

This PR targets the 1.7.0-beta4 branch, as IMO this is no-risk but high impact fix that can be shipped in 1.7.0.

How?

Swift definitions of DDRUMView and DDRUMAction were missing @objc annotation in their public init(). Definition for DDRUMView was there, but it was accidentally removed in this refactoring.

Objective-C API tests

Because unexposed or broken Objective-C APIs are recurring problem (#359, #360, #461) I did an improvement to our DatadogObjc unit tests by adding smoke tests covering the public interface in Objective-C, e.g.:

// DDConfiguration+apiTests.m

- (void)testDDConfigurationBuilderAPI {
    DDConfigurationBuilder *builder = [DDConfiguration builderWithClientToken:@"" environment:@""];
    // ...
    [builder trackUIKitRUMViews];
    [builder trackUIKitRUMViewsUsing:[CustomDDUIKitRUMViewsPredicate new]];
    [builder setRUMViewEventMapper:^DDRUMViewEvent * _Nonnull(DDRUMViewEvent * _Nonnull viewEvent) {
        viewEvent.view.url = @"";
        return viewEvent;
    }];
    // ...
    [builder setWithBatchSize:DDBatchSizeMedium];
    [builder build];
}

From now on, when we expose a new API in DatadogObjc, we can preview its Objective-C representation right in the test file. Adding test would prevent regression on eventual refactoring and ensure that the API is exposed properly.

Review checklist

• Feature or bugfix MUST have appropriate tests (unit, integration)
• Make sure each commit and the PR mention the Issue number or JIRA reference

[maxep]

Looks good! I trust you on the API coverage in the smoke tests :)

[ncreated]

Looks good! I trust you on the API coverage in the smoke tests :)

Actually, I only covered SDK configuration and RUM instrumentation APIs. This is already a lot and with Logging and Tracing being quite old features, IMO we can consider it good for now. I also created RUMM-1586 where we can add missing coverage for Logging and Tracing and think of solution / automation for ensuring that new APIs are always covered.