Fix outputs of merger - anyOf missing types

[robcxyz]

Convert any Optional field which is converted to a anyOf to its base type.

                      "transactions_24h": {
                        "title": "Transactions 24H",
                        "anyOf": [
                          {
                            "type": "int"
                          },
                          {
                            "type": null
                          }
                        ]
                      },
                      "transactions_7d": {
                        "title": "Transactions 7D",
                        "anyOf": [
                          {},
                          {}
                        ]
                      },