Help: add_custom_command(TARGET) does not support USES_TERMINAL

Build events are attached to existing build statements so we cannot
independently control the job pool.

Issue: #25040

Help/command/add_custom_command.rst

@@ -478,7 +478,7 @@ target is already built, the command will not execute.
                      [BYPRODUCTS [files...]]
                      [WORKING_DIRECTORY dir]
                      [COMMENT comment]
-                     [VERBATIM] [USES_TERMINAL]
+                     [VERBATIM]
                      [COMMAND_EXPAND_LISTS])
 
 This defines a new command that will be associated with building the