Remove pkg_resource and replace for importlib.metadata

[Rodrigo-Novas]

Describe your environment

Docker environment
Image so: ubuntu:20.04
Python version: 3.9

Otel dependencies:

opentelemetry-api = "^1.14.0"
opentelemetry-semantic-conventions = "0.41b0" # At the moment there are no releases without beta
opentelemetry-instrumentation-urllib3 = "0.41b0" # At the moment there are no releases without beta
opentelemetry-instrumentation-httpx = "0.41b0" # At the moment there are no releases without beta

Steps to reproduce

Instrument any app and run it, it will throws a warning deprecation message about pkg_resource.

I created a CM of spans with something like this:

from opentelemetry import trace
@contextlib.contextmanager
def create_span(tracer: trace.Tracer) -> Generator:
    "Start the span as current span."
    name = "name"
    _kind = "kind"
    with tracer.start_as_current_span(
        name,
        kind=_kind,
        record_exception=False,
    ) as current_span:
        yield current_span

What is the expected behavior?

Otel doesnt throws a deprecationWarning

What is the actual behavior?

The output is a deprecation warning:

DeprecationWarning: pkg_resources is deprecated as an API. See https://setuptools.pypa.io/en/latest/pkg_resources.html

Additional context

Use of pkg_resources is deprecated

[Rodrigo-Novas]

I created a fix about this on #2181

[theunkn0wn1]

FYI pkg_resources is deprecated AND REMOVED in modern python versions.
This package now depends on an undeclared dependency and is thus broken.

backend        |     from opentelemetry.instrumentation.sqlalchemy import SQLAlchemyInstrumentor
backend        |   File "/home/nonroot/.local/lib/python3.12/site-packages/opentelemetry/instrumentation/sqlalchemy/__init__.py", line 105, in <module>
backend        |     from opentelemetry.instrumentation.instrumentor import BaseInstrumentor
backend        |   File "/home/nonroot/.local/lib/python3.12/site-packages/opentelemetry/instrumentation/instrumentor.py", line 27, in <module>
backend        |     from opentelemetry.instrumentation.dependencies import (
backend        |   File "/home/nonroot/.local/lib/python3.12/site-packages/opentelemetry/instrumentation/dependencies.py", line 4, in <module>
backend        |     from pkg_resources import (
backend        | ModuleNotFoundError: No module named 'pkg_resources'