fix(sink): fix sink serde json f32

[xxhZs]

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What's changed and what's your intention?

#14365
Because we have some downstream sinks that save as JSON strings instead of f32, it causes the error mentioned in this issue.
Related sinks: Redis, Elasticsearch,

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[xiangjinwu]

See #6412

It is WRONG EXPECTATION for f32 / f64 to be lossless, for values like 1.1 that cannot be represented by limited number of bits in binary. If the user do need precise number, they should be using the decimal type.

The arbitrary_precision feature of serde_json, as well as a future similar option in our own jsonbb, is also meant for decimal. It is just an unfortunate fact that json only has a single number type, which according to RFC 8259, may only have good interoperability within IEEE 754 double precision range.