snippet for errors.Is and errors.As

[igorcafe]

Is your feature request related to a problem? Please describe.
Not exactly.
I love the extension snippets, I use iferr all the time and I miss a snippet to errors.Is and As.

Describe the solution you'd like
Suggestion:
erris -> if errors.Is(err, <cursor>) { ... }
erras -> if errors.As(err, &<cursor>) { ... }

Describe alternatives you've considered
Typing it manually.

Additional context
Add any other context or screenshots about the feature request here.