getSerializedNodes - number as node property type

[joaquinvietto]

Describe the bug
When a node has a property of type integer which value is zero, then the property is not included in node.props by getSerializedNodes function.

To Reproduce
Steps to reproduce the behavior:

1. Imagine a node called myNode which has a property called myProp that stores a number.
2. Set te value of myProp as zero, like: setProp((p) => { p[myProp] = 0; })
3. Execute getSerializedNodes()
4. Check the properties of myNode in the result of getSerializedNodes.
5. The property myProp is not included.

Expected behavior
In the result of getSerializedNodes, the node myNode should include a prop called myProp which value is zero.

Your environment

Software	Version(s)
craft.js	0.1.0-beta.11
React	17.0.1