docs: add bolha.us server to readme (#2191)

README.md

@@ -66,6 +66,7 @@ These are known deployments using Elk as an alternative Web client for Mastodon
 - [elk.aus.social](https://elk.aus.social) - Use Elk for the `aus.social` Server
 - [elk.mstdn.ca](https://elk.mstdn.ca) - Use Elk for the `mstdn.ca` Server
 - [elk.mastodonapp.uk](https://elk.mastodonapp.uk) - Use Elk for the `mastodonapp.uk` Server
+- [elk.bolha.us](https://elk.bolha.us) - Use Elk for the `bolha.us` Server
 
 > **Note**: Community deployments are **NOT** maintained by the Elk team. It may not be synced with Elk's source code. Please do your own research about the host servers before using them.