chore: bump optional mermaid dep (#1201)

[![PR App][icn]][demo] | Fix RM-14044
:-------------------:|:----------:

## 🧰 Changes

missed this from #1199

## 🧬 QA & Testing

- [Broken on production][prod].
- [Working in this PR app][demo].


[demo]: https://markdown-pr-PR_NUMBER.herokuapp.com
[prod]: https://SUBDOMAIN.readme.io
[icn]:
https://user-images.githubusercontent.com/886627/160426047-1bee9488-305a-4145-bb2b-09d8b757d38a.svg

Author: trishaprile

package-lock.json

@@ -154,7 +154,7 @@
     ]
   },
   "optionalDependencies": {
-    "mermaid": "^11.3.0"
+    "mermaid": "^11.12.0"
   },
   "overrides": {
     "@readme/markdown-legacy": {