build: add dashboard firebase functions (#4806)

* build: add dashboard firebase functions

* Adds a new folder for the dashboard project that for now only contains firebase functions.
* The firebase functions will be used to securely make API calls to the Github API (e.g payload status)
* Functions will be automatically deployed as same as screenshot functions.

* Address feedback

tools/dashboard/functions/github/github-status.ts

@@ -0,0 +1,43 @@
+import {config} from 'firebase-functions';
+
+const request = require('request');
+const {version, name} = require('../package.json');
+
+/** API token for the Github repository. Required to set the github status on commits and PRs. */
+const repoToken = config().repoToken;
+
+/** Data that must be specified to set a Github PR status. */
+export type GithubStatusData = {
+  result: boolean;
+  name: string;
+  description: string;
+  url: string;
+};
+
+/** Function that sets a Github commit status */
+export function setGithubStatus(commitSHA: string, data: GithubStatusData) {
+  const state = data.result ? 'success' : 'failure';
+
+  const requestData = JSON.stringify({
+    state: state,
+    target_url: data.url,
+    context: data.name,
+    description: data.description
+  });
+
+  const headers = {
+    'Authorization': `token ${repoToken}`,
+    'User-Agent': `${name}/${version}`,
+    'Content-Type': 'application/json',
+    'Content-Length': Buffer.byteLength(requestData)
+  };
+
+  return new Promise((resolve) => {
+    request({
+      url: `https://api.github.com/repos/angular/material2/statuses/${commitSHA}`,
+      method: 'POST',
+      form: requestData,
+      headers: headers
+    }, (error: any, response: any) => resolve(response.statusCode));
+  });
+}