[DOCUMENTATION] Fixed target JAR path

## What changes were proposed in this pull request?

Mentioned Scala version in the sbt configuration file is 2.11, so the path of the target JAR should be `/target/scala-2.11/simple-project_2.11-1.0.jar`

## How was this patch tested?

n/a

Author: prabs <prabsmails@gmail.com>
Author: Prabeesh K <prabsmails@gmail.com>

Closes #13554 from prabeesh/master.

docs/quick-start.md

@@ -289,13 +289,13 @@ $ find .
 # Package a jar containing your application
 $ sbt package
 ...
-[info] Packaging {..}/{..}/target/scala-2.10/simple-project_2.10-1.0.jar
+[info] Packaging {..}/{..}/target/scala-{{site.SCALA_BINARY_VERSION}}/simple-project_{{site.SCALA_BINARY_VERSION}}-1.0.jar
 
 # Use spark-submit to run your application
 $ YOUR_SPARK_HOME/bin/spark-submit \
   --class "SimpleApp" \
   --master local[4] \
-  target/scala-2.10/simple-project_2.10-1.0.jar
+  target/scala-{{site.SCALA_BINARY_VERSION}}/simple-project_{{site.SCALA_BINARY_VERSION}}-1.0.jar
 ...
 Lines with a: 46, Lines with b: 23
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