Fix FEX access untagged fault parsing - #482

Integration Test Summary

A focused GitLab integration run was completed for access_untagged_check against commit df13276464d4d8990b0525c1d5816f38fbd0ad46.

• Python 2.7 and Python 3.8 unit tests passed.
• All seven integration scenarios executed the intended focused check.
• The original append() TypeError did not recur.
• No validator ERROR !! results were observed.
• Each scenario correctly processed and displayed one legitimate F0467 finding as FAIL - OUTAGE WARNING!!, including the parsed interface information and recommended action.

The pipeline’s overall failure was caused by test-environment availability:

• One required fabric consistently failed its initial APIC query because its local session-token mount was unavailable.
• Other required fabrics encountered intermittent SSH authentication or socket-timeout failures.
• Nine optional fabrics per scenario reported connection warnings; the integration runner explicitly excluded these from validator errors.

No customer names, fabric identifiers, addresses, tenants, application profiles, or EPG names are included in this summary. The focused validation indicates that the code fix works as intended.