Float deserialization fails when no trailing characters are present

[ryan-summers]

When deserializing a simple float JSON (for example, 1.0 is valid JSON), an EofWhileParsingFloat will be raised. This occurs because the float parser expects some non-numeric data after the float.

However, an EOF is considered an acceptable terminator for a floating point number. We should update float parsing to return the current string if EOF is encountered instead of throwing an error.