STYLE: adjust ordering of 'find' command arguments

- use -name test before -type test to avoid calling stat(2) on every file.
- use -delete instead of -exec rm to avoid forking

tutorials/Allclean

@@ -4,10 +4,14 @@ cd ${0%/*} || exit 1    # Run from this directory
 echo "--------"
 echo "Cleaning tutorials ..."
 echo "Removing backup files"
-find . -type f \( -name "*~" -o -name "*.bak" \) -exec rm {} \;
-find . \( -name core -o -name 'core.[1-9]*' \) -exec rm {} \;
-find . \( -name '*.pvs' -o -name '*.OpenFOAM' \) -exec rm {} \;
-rm logs testLoopReport > /dev/null 2>&1
+
+find . \( \
+    -name '*~' -o -name '*.bak'         \
+    -name core -o -name 'core.[1-9]*'   \
+    -name '*.pvs' -o -name '*.OpenFOAM' \
+    \) -type f -delete
+
+rm -f logs testLoopReport > /dev/null 2>&1
 
 foamCleanTutorials cases