Update README.md

Former-commit-id: 595e66326578af07ba8136450a27f66e0b29bfa5

README.md

@@ -8,7 +8,7 @@ draw.io uses the [mxGraph library](https://github.com/jgraph/mxgraph) as the bas
 
 License
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-draw.io is licensed under the GPL v3.
+draw.io is licensed under the Apache v2.
 
 Development
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