[IOS-XR] Fix show vrf all detail parser - capture all interface names

[Kani999]

Description

Enhance interface parsing in 'show vrf all detail' parser

Implemented a general regex pattern to capture all interface names:

• Replaced the previous regex that relied on specific interface prefixes (e.g., Gi, Bun, Ten, etc.) with a more general pattern r'^(?P<intf>[A-Za-z][-A-Za-z0-9/.:]+)$'.
  • This allows the parser to match any interface name, accommodating various naming conventions and ensuring that all interfaces are properly captured.
• Introduced in_interfaces_section flag for accurate section tracking:
  • Initialized in_interfaces_section = False at the beginning of the parsing process.
  • Set in_interfaces_section = True upon encountering the Interfaces: line.
  • Used this flag to determine when interface lines should be parsed.
  • When a non-interface line is encountered within the Interfaces section, set in_interfaces_section = False
  • This ensures that the parser continues to process the current line with other parsing rules, preventing the omission of critical sections like address families and route targets.

Motivation and Context

Replaced the previous regex that relied on specific interface prefixes (e.g., Gi, Bun, Ten, etc.) with a more general pattern

Checklist:

• I have updated the changelog.
• I have updated the documentation (If applicable).
• I have added tests to cover my changes (If applicable).
• All new and existing tests passed.
• All new code passed compilation.

Closes #910