Use tmpdir in tools/change-chart-version.sh

Change-Id: I03dbc0bf95e82db7fee81dcdc0f71b51dcc7cccb
Signed-off-by: garciadeblas <gerardo.garciadeblas@telefonica.com>
diff --git a/tools/change-chart-version.sh b/tools/change-chart-version.sh
index acafe02..5e35b35 100755
--- a/tools/change-chart-version.sh
+++ b/tools/change-chart-version.sh
@@ -27,7 +27,7 @@
 
 BRANCH_NAME="v$(echo $NEW_VERSION | grep -oE '[0-9]+\.[0-9]+')"
 
-BASE_FOLDER=$(mktemp -d change-chart-version.XXXXXX)
+BASE_FOLDER=$(mktemp --tmpdir -d change-chart-version.XXXXXX)
 pushd $BASE_FOLDER
 
 if [ -n "$GIT_PASSWORD" ]; then