Remove redundant assertion in the method freeTempLocal

[ApsarasX]

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• I've added my name and email to the NOTICE file

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I think the last assertion is redundant in the method freeTempLocal.

Neither local nor local.index was modified between the two assertions below.

assemblyscript/src/flow.ts

Lines 376 to 450 in 3ff1003

	assert(local.index >= 0);
	var parentFunction = this.parentFunction;
	var temps: Local[];
	assert(local.type != null); // internal error
	local.resetTemporaryName();
	switch (<u32>local.type.toRef()) {
	case <u32>TypeRef.I32: {
	let tempI32s = parentFunction.tempI32s;
	if (tempI32s) temps = tempI32s;
	else parentFunction.tempI32s = temps = [];
	break;
	}
	case <u32>TypeRef.I64: {
	let tempI64s = parentFunction.tempI64s;
	if (tempI64s) temps = tempI64s;
	else parentFunction.tempI64s = temps = [];
	break;
	}
	case <u32>TypeRef.F32: {
	let tempF32s = parentFunction.tempF32s;
	if (tempF32s) temps = tempF32s;
	else parentFunction.tempF32s = temps = [];
	break;
	}
	case <u32>TypeRef.F64: {
	let tempF64s = parentFunction.tempF64s;
	if (tempF64s) temps = tempF64s;
	else parentFunction.tempF64s = temps = [];
	break;
	}
	case <u32>TypeRef.V128: {
	let tempV128s = parentFunction.tempV128s;
	if (tempV128s) temps = tempV128s;
	else parentFunction.tempV128s = temps = [];
	break;
	}
	case <u32>TypeRef.Funcref: {
	let tempFuncrefs = parentFunction.tempFuncrefs;
	if (tempFuncrefs) temps = tempFuncrefs;
	else parentFunction.tempFuncrefs = temps = [];
	break;
	}
	case <u32>TypeRef.Externref: {
	let tempExternrefs = parentFunction.tempExternrefs;
	if (tempExternrefs) temps = tempExternrefs;
	else parentFunction.tempExternrefs = temps = [];
	break;
	}
	case <u32>TypeRef.Anyref: {
	let tempAnyrefs = parentFunction.tempAnyrefs;
	if (tempAnyrefs) temps = tempAnyrefs;
	else parentFunction.tempAnyrefs = temps = [];
	break;
	}
	case <u32>TypeRef.Eqref: {
	let tempEqrefs = parentFunction.tempEqrefs;
	if (tempEqrefs) temps = tempEqrefs;
	else parentFunction.tempEqrefs = temps = [];
	break;
	}
	case <u32>TypeRef.I31ref: {
	let tempI31refs = parentFunction.tempI31refs;
	if (tempI31refs) temps = tempI31refs;
	else parentFunction.tempI31refs = temps = [];
	break;
	}
	case <u32>TypeRef.Dataref: {
	let tempDatarefs = parentFunction.tempDatarefs;
	if (tempDatarefs) temps = tempDatarefs;
	else parentFunction.tempDatarefs = temps = [];
	break;
	}
	default: throw new Error("concrete type expected");
	}
	assert(local.index >= 0);