Revert `tests/testdata` changes and address flake8 issues

tests/testdata/wnli-v0-res.json

-{"results": {"wnli": {"acc": 0.3380281690140845, "acc_stderr": 0.05653887739133514}}, "versions": {"wnli": 0}}
+{"results": {"wnli": {"acc": 0.3380281690140845, "acc_stderr": 0.05653887739133514}}, "versions": {"wnli": 0}}
\ No newline at end of file

tests/testdata/wnli-v1-loglikelihood

-8a0f81661d2ab2334bbc8031fac31c0c8882f1d9271dd51599d21dfdbb726dea
+8a0f81661d2ab2334bbc8031fac31c0c8882f1d9271dd51599d21dfdbb726dea
\ No newline at end of file

tests/testdata/wnli-v1-res.json

-{"results": {"wnli": {"acc": 0.5633802816901409, "acc_stderr": 0.0592793555841297}}, "versions": {"wnli": 1}}
+{"results": {"wnli": {"acc": 0.5633802816901409, "acc_stderr": 0.0592793555841297}}, "versions": {"wnli": 1}}
\ No newline at end of file

tests/testdata/wsc-v0-loglikelihood

-45865468eff5ca31e6a050947a6b3310d9d5ed19d0f2e578a32ecaf1c768600f
+45865468eff5ca31e6a050947a6b3310d9d5ed19d0f2e578a32ecaf1c768600f
\ No newline at end of file

tests/testdata/wsc-v0-res.json

-{"results": {"wsc": {"acc": 0.5480769230769231, "acc_stderr": 0.049038186969314335}}, "versions": {"wsc": 0}}
+{"results": {"wsc": {"acc": 0.5480769230769231, "acc_stderr": 0.049038186969314335}}, "versions": {"wsc": 0}}
\ No newline at end of file

tests/testdata/wsc273-v0-loglikelihood

-26450d414c4581feb51a09882080e7a9b95882e7eab47b1751a4a6024b5a60ee
+26450d414c4581feb51a09882080e7a9b95882e7eab47b1751a4a6024b5a60ee
\ No newline at end of file

tests/testdata/wsc273-v0-res.json

-{"results": {"wsc273": {"acc": 0.5164835164835165, "acc_stderr": 0.0303004740355766}}, "versions": {"wsc273": 0}}
+{"results": {"wsc273": {"acc": 0.5164835164835165, "acc_stderr": 0.0303004740355766}}, "versions": {"wsc273": 0}}
\ No newline at end of file