update shell scripts according to shellcheck recommendations and minor cleanup

util/publish.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/bin/sh
 set -e
 
 ARG=""
@@ -6,26 +6,21 @@ if test "$1" != "--do-it"; then
    ARG="--dry-run --allow-dirty"
 fi
 
-cd src/uucore/
-cargo publish $ARG
-cd -
-sleep 2s
-
-cd src/uucore_procs/
-cargo publish $ARG
-cd -
-sleep 2s
-
-cd src/uu/stdbuf/src/libstdbuf/
-cargo publish $ARG
-cd -
-sleep 2s
+for dir in src/uucore/ src/uucore_procs/ src/uu/stdbuf/src/libstdbuf/ ; do
+    (   cd "$dir"
+        #shellcheck disable=SC2086
+        cargo publish $ARG
+    )
+    sleep 2s
+done
 
 PROGS=$(ls -1d src/uu/*/)
 for p in $PROGS; do
-    cd $p
-    cargo publish $ARG
-    cd -
+    (   cd "$p"
+        #shellcheck disable=SC2086
+        cargo publish $ARG
+    )
 done
 
+#shellcheck disable=SC2086
 cargo publish $ARG