include `body_string_key_content` doesn't exist

[RedCMD]

https://github.com/jeff-hykin/better-snippet-syntax/blob/29fe32fb5e1f1329a9fb63ba23983ba3ad19b2fc/autogenerated/jsonc.tmLanguage.json#L6877

I assume it meant #string_key_content? https://github.com/jeff-hykin/better-snippet-syntax/blob/29fe32fb5e1f1329a9fb63ba23983ba3ad19b2fc/autogenerated/jsonc.tmLanguage.json#L7425

[RedCMD]

this causes all key strings inside the body object to fail

{
    "body": {
        "scope": "scope",
        "prefix": "prefix",
        "body": {
            "key": "snippet"
        },
        "description": "description"
    }
}