proposalToJSON shouldn't fail when it cannot fetch data from block explorer(s)

[aaronmgdr]

Package

@celo/celocli

Have you ensured that all of these are up to date?

• the package you are using

What version of the package are you on?

No response

What command or function is the bug in?

governaance:show

Operating System

None

Describe the bug

This is actually in the celo/governance package (or explorer?) Instead of throwing when source cant be found instead we want to display the raw tx data.