Benchmarks are not compatible with with python 3.10

Multiple benchmarks contain incompatibilities with python 3.10. All of them seem to be due to using removed aliases from collections module, which should use collections.abc module instead. A list of affected files:

multithread/bottle/bottle.py
unladen_swallow/lib/django/django/core/paginator.py
unladen_swallow/lib/django/django/db/models/sql/query.py
unladen_swallow/lib/html5lib/html5lib/_trie/_base.py
unladen_swallow/lib/html5lib/html5lib/treebuilders/dom.py