Update styles for Income popup

[Miffael]

update styles for Income popup:

[ ] In the dev version of Dollar Street, the word by is written inside of the dropdown. The drop down itself should only have the word income in it
[ ] Remove the arrow after Dollar.
[ ] Change from Dollar to USD - American Dollar
[ ] Add (PPP) in title above it
[ ] Remove unit after the word time
[ ] Add “per adult in each home” under time dropdown
[ ] Move the info to the left bottom
[ ] Remove the extra row “Income” at the top in the dropdown
[ ] When clicking on the dropdown to change time unit, change the look of the dropped