[firebase-release] Removed change log and reset repo after 3.13.0 release

Author: google-oss-bot

CHANGELOG.md

@@ -1,18 +0,0 @@
-- Adds `serviceAccount` option to `runtimeOptions` to specify which service account Cloud Function should use at runtime. For example:
-
-```
-const functions = require('firebase-functions');
-
-exports.myFunction = functions.runWith({
-    serviceAccount: '[email protected]'
-    // OR
-    // serviceAcount: 'test-sa@"
-    // OR
-    // serviceAccount: 'default'
-  })
-
-```
-
-Requires [email protected] or later. Thanks @egor-miasnikov!
-
-- Upgrades `highlight.js` to `10.4.1` to fix a vulnerability.