Add quotes to variable assignment (as requested by @TheBlueMatt)

contrib/verify-commits/verify-commits.sh

@@ -33,7 +33,7 @@ fi
 
 NO_SHA1=1
 PREV_COMMIT=""
-INITIAL_COMMIT=${CURRENT_COMMIT}
+INITIAL_COMMIT="${CURRENT_COMMIT}"
 
 while true; do
 	if [ "$CURRENT_COMMIT" = $VERIFIED_ROOT ]; then