Image used in another place

Author: frank-at-adacore

courses/spark_essentials/050_flow_analysis/02-flow_analysis.rst

@@ -6,7 +6,7 @@ Flow Analysis
 Uncontrolled Data Visibility Problem
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-.. image:: subprograms_accessing_global.png
+.. image:: subprograms_accessing_global.svg
 
 * Effects of changes are **potentially pervasive** so one must understand
   everything before changing anything