add a promotion image

Author: kyoh86

README.md

@@ -1,6 +1,8 @@
 # exportloopref
 
 An analyzer that finds exporting pointers for loop variables.
+![](https://repository-images.githubusercontent.com/256768552/a1c5bb80-dd73-11eb-9453-e520f517e730)
+Pin them all!
 
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