Bug/funding validation failure

[alfetopito]

Description

3 bug fixes

1 Attempt to fix reported user error

Was not able to reproduce issue. Still, made the validation more resilient against null values. Worst case it'll show an error message instead, giving at least some feedback.

2 Issue with price estimation breaking the app

The one I thought I fixed on https://github.com/gnosis/safe-cmm-app-react/pull/234 Hard to reproduce, got it again, and I think the reason was because the decimal value ends up being Infinity. That case is now covered.

3 Trying to fetch prices for invalid amounts

Another one that in some circumstances causes the app to crash. The copy/paste issue Graeme discovered. To reproduce, copy the estimated price amount and paste into any input field. It should not crash anymore!

Background

N/A

[ghost]

Travis automatic deployment:

• 🔐 Safe app link: To be added as a custom app on Safe Multisig Rinkeby, Mainnet or xDai
• 📖 Storybook: Component stories