Generic.WhiteSpace.ScopeIndent: Fix multi-line extends/implements indentation

[jrchamp]

Description

Scope indentation for multi-line declarations was not working. extends and implements are "children" of the oo scope tokens (for example, class/interface), so when they appear on a separate line, they were not being indented appropriately. Additionally, their "siblings", the name tokens were ignored or sometimes skipped completely.

This PR adds tests for multi-line OO Scope Tokens, adds logic so indentation is correctly checked, and reworks the logic that was causing anonymous class tokens to be skipped.

Suggested changelog entry

Generic.WhiteSpace.ScopeIndent: Fix multi-line extends/implements indentation

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
  • This change is only breaking for integrators, not for external standards or end-users.
• Documentation improvement

PR checklist

• I have checked there is no other PR open for the same change.
• I have read the Contribution Guidelines.
• I grant the project the right to include and distribute the code under the BSD-3-Clause license (and I have the right to grant these rights).
• I have added tests to cover my changes.
• I have verified that the code complies with the projects coding standards.
• [Required for new sniffs] I have added XML documentation for the sniff.
• I have opened a sister-PR in the documentation repository to update the Wiki.