Add examples and description for Postgres login subcommand (spiceai#518)

spiceaidocs/docs/cli/reference/login.md

@@ -1,6 +1,6 @@
 ---
-title: 'login'
-sidebar_label: 'login'
+title: "login"
+sidebar_label: "login"
 pagination_prev: null
 pagination_next: null
 ---
@@ -18,7 +18,7 @@ spice login [command] [flags]
 - `-h`, `--help` Print this help message
 - `-k`, `--key` string API key (for spice.ai)
 
-#### Available Commands
+#### Available Commands To Connect to Other Services
 
 - `abfs` Login to a Azure Storage Account
 - `databricks` Login to a Databricks instance
@@ -30,14 +30,40 @@ spice login [command] [flags]
 - `snowflake` Login to a Snowflake warehouse
 - `spark` Login to a Spark Connect remote
 
-#### Examples
+### Examples
 
 ```shell
 spice login
 ```
 
-### Additional Example
+#### Additional Example
 
 ```shell
 spice login --key <API_KEY>
 ```
+
+### Examples for Other Services
+
+### Postgres
+
+**Example 1**:
+
+```shell
+spice login postgres --password <password>
+```
+
+**Example 2**:
+
+```shell
+spice login postgres -p <password>
+```
+
+**Required Flags**:
+
+- `-p`, `--password` Password to your postgres user
+
+**Sample Output**:
+
+```
+2024/12/18 13:59:10 INFO Successfully logged in to Pg
+```