config/sql: Add example configuration links to auth

Author: sirainen

docs/core/config/auth/databases/sql.md

@@ -3,6 +3,15 @@ layout: doc
 title: SQL
 dovecotlinks:
   auth_sql: SQL authentication database
+  auth_mysql:
+    hash: mysql
+    text: MySQL authentication
+  auth_postgresql:
+    hash: postgresql
+    text: PostgreSQL authentication
+  auth_sqlite:
+    hash: sqlite
+    text: Sqlite authentication
 ---
 
 # SQL Database (`sql`)

docs/core/config/sql/mysql.md

@@ -16,6 +16,10 @@ headers installed.
 
 For MariaDB, you need to have compatibility headers installed.
 
+## Example Configuration
+
+See [[link,auth_mysql]].
+
 ## Settings
 
 <SettingsComponent tag="sql-mysql" />

docs/core/config/sql/postgresql.md

@@ -12,6 +12,10 @@ Driver name is `postgresql`.
 To compile support for this driver, you need PostgreSQL client library and
 headers.
 
+## Example Configuration
+
+See [[link,auth_postgresql]].
+
 ## Settings
 
 <SettingsComponent tag="sql-postgresql" />

docs/core/config/sql/sqlite.md

@@ -11,6 +11,10 @@ Driver name is `sqlite`.
 
 To compile support for this driver. you need sqlite library and headers.
 
+## Example Configuration
+
+See [[link,auth_sqlite]].
+
 ## Settings
 
 <SettingsComponent tag="sql-sqlite" />