loosen Pillow version from ==9.1.0 to >=9.0

requirements.txt

 arkindex-client==1.0.8
 peewee==3.14.10
-Pillow==9.1.0
+Pillow>=9.0
 python-gitlab==2.7.1
 python-gnupg==0.4.8
 sh==1.14.2