<!-- Describe the issue -->
`getrawtransaction` fails
<!--- What behavior did you expect? -->
Return decoded raw tx
<!--- What was the actual behavior (provide screenshots if the issue is GUI-related)? -->
* `bitcoin-qt -prune=8192  -server -rpcuser=rpc -rpcpassword=rpc -onlynet=ipv4 -rpcbind=127.0.0.1:18332 -testnet`
  * BTC 0.18.0
  * `getrawtransaction b423b2b22d6d74376de2887c07f7c84ae890a93d541fcc6dbf3686f2923b2753 1`
![image](https://user-images.githubusercontent.com/3670331/58841021-658d7180-8668-11e9-9f9f-ed1f794070ea.png)
  * BTC 0.17.1
  * `getrawtransaction b423b2b22d6d74376de2887c07f7c84ae890a93d541fcc6dbf3686f2923b2753 1`
![image](https://user-images.githubusercontent.com/3670331/58841089-9ff70e80-8668-11e9-8a68-5022631b43d7.png)

<!--- How reliably can you reproduce the issue, what are the steps to do so? -->
Request `getrawtransaction`.
<!-- What version of Bitcoin Core are you using, where did you get it (website, self-compiled, etc)? -->
Official from site.
<!-- What type of machine are you observing the error on (OS/CPU and disk type)? -->
`Linux pentagon 4.9.0-9-amd64 #1 SMP Debian 4.9.168-1+deb9u2 (2019-05-13) x86_64 GNU/Linux`, u5200, 2x8Gb, SSD
<!-- For the GUI-related issue on Linux provide names and versions of a distro, a desktop environment and a graphical shell (if relevant). -->
QT
<!-- Any extra information that might be useful in the debugging process. -->
<!--- This is normally the contents of a `debug.log` or `config.log` file. Raw text or a link to a pastebin type site are preferred. -->

{
    const RPCHelpMan help{"decodescript",
                "\nDecode a hex-encoded script.\n",
                {
                    {"hexstring", RPCArg::Type::STR_HEX, RPCArg::Optional::NO, "the hex-encoded script"},
                },
                RPCResult{
            "{\n"
            "  \"asm\":\"asm\",          (string) Script public key\n"
            "  \"type\":\"type\",        (string) The output type (e.g. "+GetAllOutputTypes()+")\n"
            "  \"reqSigs\": n,         (numeric) The required signatures\n"
            "  \"addresses\": [        (json array of string)\n"
            "     \"address\"          (string) bitcoin address\n"
            "     ,...\n"
            "  ],\n"
            "  \"p2sh\":\"str\"          (string) address of P2SH script wrapping this redeem script (not returned if the script is already a P2SH).\n"
            "  \"segwit\": {           (json object) Result of a witness script public key wrapping this redeem script (not returned if the script is a P2SH or witness).\n"
            "    \"asm\":\"str\",        (string) String representation of the script public key\n"
            "    \"hex\":\"hexstr\",     (string) Hex string of the script public key\n"
            "    \"type\":\"str\",       (string) The type of the script public key (e.g. witness_v0_keyhash or witness_v0_scripthash)\n"
            "    \"reqSigs\": n,       (numeric) The required signatures (always 1)\n"
            "    \"addresses\": [      (json array of string) (always length 1)\n"
            "      \"address\"         (string) segwit address\n"
            "       ,...\n"
            "    ],\n"