Drop the sponsor banner

The README opened on a banner reading "The best undetectable browser", a
superlative nothing here or in the packages benchmarks, sitting directly above
the section that spends a paragraph explaining the browser is one input into a
risk score among several. invisible_playwright is still linked where it belongs,
under the pieces the project is made of.

The image stays in assets/ since other repositories reference that URL.

Author: feder-cr

README.md

@@ -1,11 +1,3 @@
-<p align="center"><sub><b>SPONSOR</b></sub></p>
-
-<p align="center">
-  <a href="https://github.com/feder-cr/invisible_playwright"><img src="https://raw.githubusercontent.com/feder-cr/Jobs_Applier_AI_Agent_AIHawk/main/assets/invisible-playwright-banner.png" alt="invisible_playwright - the best undetectable browser" width="880"></a>
-</p>
-
----
-
 <div align="center">
 
 # AIHawk