[llvm-rc] [test] Fix a misplaced extra argument in a test comment. NFC.

This was added accidentally in
64bc44f, while mass-adding the
-no-preprocess argument to the llvm-rc invocations in the tests.

llvm/test/tools/llvm-rc/tag-menu.test

@@ -1,7 +1,7 @@
 ; RUN: llvm-rc -no-preprocess /FO %t -- %p/Inputs/tag-menu.rc
 ; RUN: llvm-readobj %t | FileCheck %s --check-prefix=MENU
 
-; Test running llvm-rc -no-preprocess without an explicit output file.
+; Test running llvm-rc without an explicit output file.
 ; RUN: cp %p/Inputs/tag-menu.rc %t.implicit.rc
 ; RUN: llvm-rc -no-preprocess -- %t.implicit.rc
 ; RUN: llvm-readobj %t.implicit.res | FileCheck --check-prefix=MENU %s