author and committer are optional (if only one is given, it will be used for the other, otherwise the authenticated user will be used){
"author": {
"email": "user@example.com",
"name": "string"
},
"branch": "string",
"committer": {
"email": "user@example.com",
"name": "string"
},
"content": "string",
"dates": {
"author": "2019-08-24T14:15:22.123Z",
"committer": "2019-08-24T14:15:22.123Z"
},
"message": "string",
"new_branch": "string",
"signoff": true
}