Update docs/configuring-playbook-external-postgres.md: minor changes

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

docs/configuring-playbook-external-postgres.md

@@ -17,11 +17,10 @@ matrix_synapse_database_database: "your-postgres-server-database-name"
 
 # Rewire any other service (each `matrix-*` role) you may wish to use to use your external Postgres server.
 # Each service expects to have its own dedicated database on the Postgres server
-# and uses its own variable names (see `roles/custom/matrix-*/defaults/main.yml) for configuring Postgres connectivity.
+# and uses its own variable names (see `roles/custom/matrix-*/defaults/main.yml`) for configuring Postgres connectivity.
 ```
 
-The database (as specified in `matrix_synapse_database_database`) must exist and be accessible with the given credentials.
-It must be empty or contain a valid Synapse database. If empty, Synapse would populate it the first time it runs.
+The database (as specified in `matrix_synapse_database_database`) must exist and be accessible with the given credentials. It must be empty or contain a valid Synapse database. If empty, Synapse would populate it the first time it runs.
 
 **Note**: the external server that you specify in `matrix_synapse_database_host` must be accessible from within the `matrix-synapse` Docker container (and possibly other containers too). This means that it either needs to be a publicly accessible hostname or that it's a hostname on the same Docker network where all containers installed by this playbook run (a network called `matrix` by default). Using a local PostgreSQL instance on the host (running on the same machine, but not in a container) is not possible.