draft: Gracefully handle when multiple conditional branches are true

[brennj]

Consider the following schema:

{
  "additionalProperties": false,
  "properties": {
    "word": {
      "type": "string"
    }
  },
  "allOf": [
    {
      "if": {
        "properties": { "word": { "const": "hello" } },
        "required": ["word"]
      },
      "then": { "properties": { "word": { "maxLength": 5 } } }
    },
    {
      "if": {
        "properties": { "word": { "const": "hello" } },
        "required": ["word"]
      },
      "then": {
        "properties": { "word": { "description": "I am a description" } }
      }
    }
  ]
}

When the field word has a value of hello, you'd expect the attributes to be the following:

{
  name: 'word',
  description: 'I am a description',
  maxLength: 5
}

This in the main branch does not work at the moment correctly, because on every evaluation of successfully valid conditional branch that we apply, we also run removeConditionalStateAttributes. This means that the expected result only happens here.

But, we have no way of saying "keep the results from ALL branches before removing whats stale". It considers the previously evaluated branch as stale.

What I've done here makes a unit test for this pass... but I haven't fully battle tested. And I very much hate the solution and I'm convinced theres a better way to do this that isn't as truly abhorrent as this.