function inferUnionType(node) {
    const types = new Set()
    for (const t of node.types) {
      for (const tt of inferRuntimeType(context, t, checked)) {
        types.add(tt)
      }
    }
    return [...types]
  }
@param {import('@typescript-eslint/types').TSESTree.TSUnionType|import('@typescript-eslint/types').TSESTree.TSIntersectionType} node
@returns {string[]}