CLN: Fix ReadMe Badges
Noticed when discussing https://github.com/pandas-dev/pandas/issues/31560 our badges are written in HTML + take up a lot of vertical space on our Readme.

My branch (a lot more compact vs master):
https://github.com/alimcmaster1/pandas/tree/mcmali-readme#pandas-powerful-python-data-analysis-toolkit

I've also added a NumFocus one :) 
