[doc] add missing whitespace

Signed-off-by: Bilal Amarni <bilal.amarni@gmail.com>

docs/admin/logging/overview.md

@@ -25,7 +25,7 @@ supported:
 | `json-file` | Default logging driver for Docker. Writes JSON messages to file.                                                              |
 | `syslog`    | Syslog logging driver for Docker. Writes log messages to syslog.                                                              |
 | `journald`  | Journald logging driver for Docker. Writes log messages to `journald`.                                                        |
-| `gelf`      | Graylog Extended Log Format (GELF) logging driver for Docker. Writes log messages to a GELF endpoint likeGraylog or Logstash. |
+| `gelf`      | Graylog Extended Log Format (GELF) logging driver for Docker. Writes log messages to a GELF endpoint like Graylog or Logstash. |
 | `fluentd`   | Fluentd logging driver for Docker. Writes log messages to `fluentd` (forward input).                                          |
 | `awslogs`   | Amazon CloudWatch Logs logging driver for Docker. Writes log messages to Amazon CloudWatch Logs.                              |
 | `splunk`    | Splunk logging driver for Docker. Writes log messages to `splunk` using HTTP Event Collector.                                 |