fix: separate pylint config for opentracing example to resolve FIXME

[chimchim89]

Description

Resolves the FIXME in docs/examples/opentracing/rediscache.py.

The FIXME noted that # pylint: disable=import-error was needed because the example code was being linted under the main project's tox environment which did not have redis and redis_opentracing installed.

Changes made:

• Removed FIXME comment and # pylint: disable=import-error from rediscache.py
• Added lint-opentelemetry-opentracing-example to envlist in tox.ini
• Added dedicated [testenv:lint-opentelemetry-opentracing-example] section with:
  • Dependencies from docs/examples/opentracing/requirements.txt
  • PYTHONPATH set to example folder so local module rediscache resolves correctly
  • Clean pylint command using root .pylintrc

Type of change

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

Ran the new lint environment:

tox -e lint-opentelemetry-opentracing-example

Result: Your code has been rated at 10.00/10

Ran ruff:

tox -e ruff

Result: all checks passed.

Does This PR Require a Contrib Repo Change?

• No.

Checklist:

• Followed the style guidelines of this project
• Changelogs have been updated
• Unit tests have been added
• Documentation has been updated

[xrmx]

@chimchim89 I think you haven't pushed part of what the description says

[chimchim89]

@chimchim89 I think you haven't pushed part of what the description says

sorry for the confusion. that was a mistake on my side.

i have pushed the fix.

[tammy-baylis-swi]

Thanks! Please also add Changelog entry.

[chimchim89]

Thanks! Please also add Changelog entry.

yes, added changelog entry.