Fix minor issues in generator

[glarregay-tob]

I tried to use fuzz-utils and there were some issues that this PR aims to fix:

• Misaligned vm.warp() in the generated contract in a call template
• Dynamic array variables were redefined each time they were used. If the same tests had many calls to functions that required arrays as parameters, they were redefined each time, generating compilation errors. Now it is only defined once in each test, and only the value is set in each subsequent call.
• bool success was redefined for each single low level call, so tests could only have at most one low level call, before the compiler complained.

[tuturu-tech]

I pushed some changes:

• Added the declared_variables set to Medusa as well since I think it had the same issue.
• Updated the set and comparison to be a tuple[type, name] so that we don't mistakenly match a variable name that has a different type
• Added a sequence to each fuzzer dyn-arr corpus to reproduce the issue and test the changes

LGTM now, great work on noticing and fixing the issues!

[glarregay-tob]

Ah, yes, sorry for the lack of Medusa support, I was only using Echidna for the tests.

Regarding the variables, I assume it's not possible, but if we have two variables with the same name and different type, we will still have compilation issues when reassigning. I haven't considered this case, because variable names should be unique in the current scope, but I'll keep using the tool and report if something comes up.