Create individual issue view using Block Kit API

## Draft / Concept

### Accompanying block array

```js
{
"blocks": [
{
"type": "header",
"text": {
"type": "plain_text",
"text": "ansi-regex"
}
},
{
"type": "section",
"text": {
"type": "mrkdwn",
"text": "_Regular Expression Denial of Service (ReDoS)_"
}
},
{
"type": "section",
"text": {
"type": "mrkdwn",
"text": "*Vulnerability:*\n - - "
}
},
{
"type": "section",
"fields": [
{
"type": "mrkdwn",
"text": "*Score:*\n485"
},
{
"type": "mrkdwn",
"text": "*Priority:*\n:red_circle: High\n  "
},
{
"type": "mrkdwn",
"text": "*Snyk Identifier:*\nSNYK-JS-ANSIREGEX-1583908"
},
{
"type": "mrkdwn",
"text": "*Introduced through:*\nesdoc@1.1.0"
}
]
},
{
"type": "actions",
"elements": [
{
"type": "button",
"text": {
"type": "plain_text",
"emoji": true,
"text": "View on Snyk.io"
},
"style": "primary",
"value": "click_me_123"
},
{
"type": "button",
"text": {
"type": "plain_text",
"emoji": true,
"text": "Ignore"
},
"style": "danger",
"value": "click_me_123"
}
]
}
]
}
```