install backport of exception groups to make download_media work

chat_archiver/setup.py

@@ -9,6 +9,7 @@ setup(
 	packages=find_packages(),
 	install_requires=[
 		'argh==0.28.1',
+		"exceptiongroup", # backport from python 3.11
 		'gevent',
 		'monotonic',
 		'requests', # for emote fetching

sheetsync/setup.py

@@ -7,6 +7,7 @@ setup(
 	install_requires = [
 		"argh==0.28.1",
 		"gevent",
+		"exceptiongroup", # backport from python 3.11
 		"prometheus-client==0.7.1", # locked version as we rely on internals
 		"psycogreen",
 		"psycopg2",