Add Span Attribute Inheritance and Step Urls

Description

• Add attribute inheritance from workflow -> job -> step spans

  • Workflow attributes are passed down to job spans
  • Job attributes (including workflow attributes) are passed down to step spans
  • Each span level can override inherited attributes
  • Removed redundant attribute copying in step spans

• Add direct URLs to individual steps

  • Each step span now includes a github.job.step.url attribute
  • URLs link directly to the specific step in the GitHub Actions UI