Refer to correct docker image

Author: mmkal

readme.md

@@ -54,7 +54,7 @@ psql -c "
 psql -f node_modules/plv8-git/queries/create-git-functions.sql
 ```
 
-Note: for `create extension plv8` to work the plv8.control file must exist on your database system. You can use [the postgres-plv8 docker image](https://github.com/clkao/docker-postgres-plv8/tree/master/12-2) for development (or production, if you really want to deploy a containerised database to production). Amazon RDS instances [have the extension available](https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/CHAP_PostgreSQL.html), as does [Azure Postgres 11](https://docs.microsoft.com/en-us/azure/postgresql/concepts-extensions#postgres-11-extensions).
+Note: for `create extension plv8` to work the plv8.control file must exist on your database system. You can use [the postgres-plv8 docker image](https://github.com/clkao/docker-postgres-plv8/tree/master/11-2) for development (or production, if you really want to deploy a containerised database to production). Amazon RDS instances [have the extension available](https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/CHAP_PostgreSQL.html), as does [Azure Postgres 11](https://docs.microsoft.com/en-us/azure/postgresql/concepts-extensions#postgres-11-extensions).
 
 This will have created three postgres functions: `git_track`, `git_log` and `git_resolve`.