Reimplement the utf8 string check (#389)
Reimplement the utf8 string check (#389)

Previous implementation doesn't take care of overlong encoding

Signed-off-by: Xiaokang Qin <3dfcec240079f81899deaaacd71e5f8e6cd22316@antgroup.com>
bytecodealliance/wasm-micro-runtime,bytecodealliance/wasm-micro-runtime,bytecodealliance/wasm-micro-runtime,bytecodealliance/wasm-micro-runtime,bytecodealliance/wasm-micro-runtime,bytecodealliance/wasm-micro-runtime,bytecodealliance/wasm-micro-runtime,bytecodealliance/wasm-micro-runtime