Missed updating a language

Signed-off-by: Lynette Miles <[email protected]>

Author: esmerel

administration/configuring-fluent-bit/classic-mode/variables.md

@@ -24,7 +24,7 @@ These files are ignored if they don't exist.
 
 Create the following configuration file \(`fluent-bit.conf`\):
 
-```text
+```yaml
 [SERVICE]
     Flush        1
     Daemon       Off