Conflicting inputs on erlang build of Opentelemetry

Hi,

We use open-telemetry as a third party dependency (https://github.com/open-telemetry/opentelemetry-erlang), but are hitting a problem with the conflicting inputs check in erlang_application. The issue is caused by the opentelemetry_api_experimental and the opentelemetry_experimental both having include files names "otel_metrics.hrl". I get that might not be best practice, but I think the reasoning is that the otel_metrics.hrl inside opentelemetry_experimental is not part of the public API, so in principal outside code shouldn't care what that file is called.

For my rules, I have specified the hols in opentelemetry_experimental as part of "srcs", so they should be private:

```
erlang_application(
name = "opentelemetry_experimental",
srcs = glob(["opentelemetry/apps/opentelemetry_experimental/src/*.erl", "opentelemetry/apps/opentelemetry_experimental/include/*.hrl"]),
version = "1.2.1",
...
```

and for opentelemetry_experimental_api the hrls are listed in "includes":

```
erlang_application(
name = "opentelemetry_api_experimental",
srcs = glob(["opentelemetry/apps/opentelemetry_api_experimental/src/*.erl"]),
includes = glob(["opentelemetry/apps/opentelemetry_api_experimental/include/*.hrl"]),

```

Would it be reasonable for the conflict checker to take into account the private vs public distinction?