Send Slack Message Action

Sends a markdown message to a Slack channel.

Unlike rtCamp/action-slack-notify, this action uses slackapi/slack-github-action and does not require Docker.

Inputs

Input	Description	Required
`channel`	Slack channel (without `#`) to post the message into.	Yes
`message-markdown`	The message to send, in markdown format.	Yes

This action depends on:

LoveToKnow/slackify-markdown-action to convert markdown to Slack's mrkdwn format
slackapi/slack-github-action to send the message via chat.postMessage