Increase clickable area of dropdowns

[lukasschor]

Some users have struggled to open dropdowns, as they are clicking on the arrow icon withing a dropdown field, yet the clickable area does not include this part.

• The clickable are should be increased to the full are of the dropdown field in the following flows:

Add new owner:

• 

Send funds:

Create new Safe:

Change threshold:

[katspaugh]

Will be fixed in the Outlined Inputs.