ISTWCMS-3759: updating build script to only copy files instead of moving them

build_gesso.sh

@@ -6,11 +6,11 @@ git checkout $gesso_version
 cd ..
 
 if [ -f "gulpfile.js" ]; then
-  mv gulpfile.js gesso
+  cp gulpfile.js gesso
 fi
 
 if [ -f "packages.json" ]; then
-  mv packages.json gesso
+  cp packages.json gesso
 fi
 
 ln -s "gesso/source" "source"