Update command-line-reference.mdx for --log-prefix CLI option (#6657)

docs/pages/repo/docs/reference/command-line-reference/run.mdx

@@ -249,6 +249,27 @@ turbo run build --log-order=grouped
   You can opt out of this behavior by setting a log order of your own.
 </Callout>
 
+### `--log-prefix`
+
+`type: string`
+
+This controls the `<package>:<task>:` prefix to log lines produced when running tasks (both on execute and replay from cache). This also applies to "single package" repos where the prefix will be just `<task>:`.
+The log output when running multiple parallel tasks will be interleaved, so another method must be used to determine which task logged that line (ie enriched JSON logs) if the prefix is omitted.
+
+| option | description                               |
+| ------ | ----------------------------------------- |
+| auto   | Turbo decides based on its own heuristics |
+| none   | No prefixes                               |
+| prefix | Force prepending the prefix to logs       |
+
+```shell
+--log-prefix=none
+```
+
+```shell
+turbo run dev --log-prefix=none
+```
+
 ### `--no-cache`
 
 Default `false`. Do not cache results of the task. This is useful for watch commands like `next dev` or `react-scripts start`.