strip whitespace from comma-separated service names

[AnshulPatil2005]

Pull Request description

Fixes a bug where passing service names with spaces after commas (e.g. --services "service1, service2") would silently fail to match services. The space was being included as part of the service name, causing mismatches.

Root cause: _arg_services.split(',') in _get_services_names did not strip whitespace from each element.
Fix: Changed to [s.strip() for s in _arg_services.split(',')] in src/sugar/extensions/base.py.

solve #204

How to test these changes

run test

• pytest tests/test_ext_compose.py::test_cmd_build_services_with_spaces

Pull Request checklists

This PR is a:

• bug-fix
• new feature
• maintenance

About this PR:

• it includes tests.
• the tests are executed on CI.
• the tests generate log file(s) (path).
• pre-commit hooks were executed locally.
• this PR requires a project documentation update.

Author's checklist:

• I have reviewed the changes and it contains no misspelling.
• The code is well commented, especially in the parts that contain more
  complexity.
• New and old tests passed locally.

Additional information

Before fix: "service1, service2".split(',') → ['service1', ' service2'] — the leading space on service2 causes a lookup failure.

After fix: [s.strip() for s in "service1, service2".split(',')] → ['service1', 'service2'] — correct.

Changed file: src/sugar/extensions/base.py line 436.
Test added: tests/test_ext_compose.py::test_cmd_build_services_with_spaces.

[AnshulPatil2005]

@sanjay7178 @xmnlab Could you please review this PR when you get a chance.

Thanks.