CI: Migrate 5 shortest expect tests to e2e_subs

## Problem

Since e2e_subs default to network reuse while expect tests don't reuse networks, a seemingly quick win for CI speed up is to convert short expect tests to e2e_subs.

The story requests focusing on short expect tests under the assumption that a short test implies less conversion effort. Limiting to 5 shortest tests is somewhat haphazard and intends to limit scope.

Here's one way to find short tests: `find test -iname "*.exp" -exec wc -l {} \; | sort -h`

## Solution

## Dependencies

## Urgency