audit: fix full versioned alias name resolution in taps

[JCount]

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This fixes an issue where audit would prompt for the creation
of an already existing versioned alias while at the same time
declaring the existing alias invalid.

This can be done in one line, but it seemed less readable. I am happy to change it, however.

cc @MikeMcQuaid as this is a slight fix to his PR: #2619.

Fixes #2650.

[JCount]

The bug that this is intended to fix is the one @javian reported in #2650.

[MikeMcQuaid]

Thanks @JCount!