Merge pull request #54094 from rnhmjoj/shell

treewide: use ${stdenv.shell} instead of /bin/sh where possible

pkgs/tools/backup/flockit/default.nix

@@ -16,7 +16,7 @@ stdenv.mkDerivation rec {
     cp ./libflockit.so $out/lib
 
     (cat <<EOI
-    #!/bin/sh
+    #!${stdenv.shell}
     env LD_PRELOAD="$out/lib/libflockit.so" FLOCKIT_FILE_PREFIX=\$1 \''${@:2}
     EOI
     ) > $out/bin/flockit

pkgs/tools/backup/store-backup/default.nix

@@ -9,7 +9,7 @@
 
 # known impurity: test cases seem to bu using /tmp/storeBackup.lock ..
 
-let dummyMount = writeScriptBin "mount" "#!/bin/sh";
+let dummyMount = writeScriptBin "mount" "#!${stdenv.shell}";
 in
 
 stdenv.mkDerivation rec {