Scaffolding: fix indentation inconsistencies in generated proto files

[lumtis]

There may be different inconsistencies in the indentation for generated proto code: https://github.com/tendermint/spn/pull/294/files#r704611184 we should investigate them, fix and make generated proto files well formated. I believe 2 spaces for indentation.

Or we can check for a tool that autoformat proto code

[jaredalonzo]

I've noticed that the tx.proto's Msg service indents the first rpc by 3 tab characters whereas subsequent calls to scaffold message only indents by 1 tab character .

[salmad3]

Check formatting state of files today. We can consider an additional linting tool to enforce formatting.