Test failures in analytical decomposition transformers

[maffoo]

In #5219 I've started seeing test failures in analytic decomposition tests, see https://github.com/quantumlib/Cirq/runs/6913023342?check_suite_focus=true.

FAILED cirq-core/cirq/transformers/analytical_decompositions/two_qubit_to_fsim_test.py::test_decompose_two_qubit_interaction_into_two_b_gates[obj10]
FAILED cirq-core/cirq/transformers/analytical_decompositions/two_qubit_to_fsim_test.py::test_decompose_two_qubit_interaction_into_four_fsim_gates_equivalence[obj190-fsim_gate190]

Possibly related to recent change in default precision (#5426).

[tanujkhattar]

This doesn't seem to be fixed yet.

See: https://github.com/quantumlib/Cirq/runs/6976353468?check_suite_focus=true