Fix error with very large ints in to_jsonable

[tybug]

Noticed when investigating #3874.

Can reproduce with:

@given(st.integers(0, 1<<10000))
def test_f(n):
    pass
test_f()

...
  File "/Users/tybug/Desktop/Liam/coding/hypothesis/hypothesis-python/src/hypothesis/strategies/_internal/utils.py", line 163, in to_jsonable
    return float(obj)
           ^^^^^^^^^^
OverflowError: int too large to convert to float

[tybug]

saw a coverage flake, so tried increasing the reliability in 6c42078. 5 should have been plenty, but increasing iterations is cheap and I don't particularly want to rabbit-hole into it right now.

[Zac-HD]

Nice!