scripted-diff: Adjust documentation per top-level target output location

-BEGIN VERIFY SCRIPT-

ren() { sed -i "s|\<$1\>|$2|g" $( git grep -l "$1" :\(exclude\)./src/secp256k1 ) ; }

ren build/src/bench   build/bin
ren build/src/test    build/bin
ren build/src/qt/test build/bin
ren build/src/qt      build/bin
ren build/src         build/bin
ren build_fuzz/src/test/fuzz build_fuzz/bin

-END VERIFY SCRIPT-

doc/build-unix.md

@@ -188,6 +188,6 @@ This example lists the steps necessary to setup and build a command line only di
     cmake -B build
     cmake --build build
     ctest --test-dir build
-    ./build/src/bitcoind
+    ./build/bin/bitcoind
 
 If you intend to work with legacy Berkeley DB wallets, see [Berkeley DB](#berkeley-db) section.