Update README.md

Author: MohamedRagabAnas

docs/README.md

@@ -115,7 +115,7 @@ In the directory of [Scirpts](https://github.com/DataSystemsGroupUT/SPARKSQLRDFB
 
 ### Project Phases
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-<p align="center"><img src="images/SparkSQLRDFBenchPhases.jpg" alt="spark"> </p>
+<p align="center"><img src="docs/images/SparkSQLRDFBenchPhases.jpg" alt="spark"> </p>
 
 #### Phase#1
 In the frst phase of our work, we presented a systematic analysis of the performance of Spark-SQL query engine (mainly