Bump handlebars from 4.5.3 to 4.7.7 in /dashboard (#720)

Bumps [handlebars](https://github.com/wycats/handlebars.js) from 4.5.3 to 4.7.7.
- [Release notes](https://github.com/wycats/handlebars.js/releases)
- [Changelog](https://github.com/handlebars-lang/handlebars.js/blob/master/release-notes.md)
- [Commits](handlebars-lang/handlebars.js@v4.5.3...v4.7.7)

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Adam Janikowski <12255597+ajanikow@users.noreply.github.com>

Author: dependabot[bot]

dashboard/package-lock.json

@@ -5,7 +5,7 @@
   "dependencies": {
     "emotion": "^9.2.12",
     "eslint": "^6.5.0",
-    "handlebars": "^4.5.3",
+    "handlebars": "^4.7.7",
     "js-yaml": ">=3.13.1",
     "lodash": "^4.17.19",
     "react": "^16.10.1",