Update bootstrap.example.toml

Co-authored-by: Jakub Beránek <[email protected]>

Author: Hayden602

bootstrap.example.toml

@@ -859,7 +859,7 @@
 # Trigger a `DebugBreak` after an internal compiler error during bootstrap on Windows
 #rust.break-on-ice = true
 
-# Set the number of threads for the compiler frontend used during rustc compilation (passed to `-Zthreads`).
+# Set the number of threads for the compiler frontend used during compilation of Rust code (passed to `-Zthreads`).
 # The valid options are:
 # 0 - Set the number of threads according to the detected number of threads of the host system
 # 0 - Set the number of threads according to the detected number of threads of the host system