Fix link to CLI docs

Author: jseldess

src/main.rs

@@ -92,7 +92,7 @@ Flags
 
 LEARN MORE
 Use `bt <command> <subcommand> --help` for more information about a command.
-Read the manual at https://braintrust.dev/docs/cli
+Read the manual at https://braintrust.dev/docs/reference/cli
 
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