HADOOP-13457. Remove hardcoded absolute path for shell executable. (Chen Liang)

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/util/Shell.java

@@ -371,7 +371,7 @@ public abstract class Shell {
     String absolutePath = script.getAbsolutePath();
     return WINDOWS ?
       new String[] {"cmd", "/c", absolutePath }
-      : new String[] {"/bin/bash", bashQuote(absolutePath) };
+      : new String[] {"bash", bashQuote(absolutePath) };
   }
 
   /** a Unix command to set permission: {@value}. */