Inline verifier struct creation

[dhrubabasu]

Why this should be merged

Required for #3236

We'll need the proposerVMCtx to be passed into verifier which is nicer to construct on the fly.

How this works

Inline verifier struct creation

How this was tested

CI

[tsachiherman]

the only downside I can see here is the fact that if we were to have a dozen of places where verifier is being constructed in that way and we add another member to verifier, than we might miss adding that field to all the instances.

[marun]

the only downside I can see here is the fact that if we were to have a dozen of places where verifier is being constructed in that way and we add another member to verifier, than we might miss adding that field to all the instances.

This might be a good opportunity to invoke YAGNI, since the type is currently only constructed in a single place (outside of testing) and is not exported.