[fix] pexels: circumvent botdetection by passing referer header

As a side effect, Cloudscraper is no longer needed.
It probably only ever worked by setting the correct request headers,
so we don't really need it since we can just set the right request
headers and ciphersuites ourselves.

requirements.txt

@@ -17,4 +17,3 @@ typer==0.24.1
 isodate==0.7.2
 whitenoise==6.12.0
 typing-extensions==4.15.0
-cloudscraper==1.2.71