Don't barf when the properties file does not exist

Author: andrewor14

bin/spark-submit

@@ -48,7 +48,7 @@ export SPARK_SUBMIT_PROPERTIES_FILE=${SPARK_SUBMIT_PROPERTIES_FILE:-"$DEFAULT_PR
 # paths, library paths, java options and memory early on. Otherwise, it will
 # be too late by the time the JVM has started.
 
-if [ "$SPARK_SUBMIT_DEPLOY_MODE" == "client" ]; then
+if [[ "$SPARK_SUBMIT_DEPLOY_MODE" == "client" && -f "$SPARK_SUBMIT_PROPERTIES_FILE" ]]; then
   # Parse the properties file only if the special configs exist
   contains_special_configs=$(
     grep -e "spark.driver.extra*\|spark.driver.memory" "$SPARK_SUBMIT_PROPERTIES_FILE" | \