Revert "Pin Pillow to 10.1.0 to make Snyk happy"

This reverts commit e4af342.

This didn't fix our issue. See for more context:

#8034 (comment)

Author: chosak

requirements/libraries.txt

@@ -23,7 +23,6 @@ govdelivery==1.4.0
 Jinja2==3.1.2
 lxml==4.9.1
 opensearch-py==2.2.0
-Pillow==10.1.0
 psycopg2-binary==2.8.6
 python-dateutil==2.8.2
 regdown==1.0.7