Update README.md

Author: app-generator

README.md

@@ -4,6 +4,14 @@ Simple **Flask API Boilerplate** enhanced with `JWT` authentication, `OAuth` via
 
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+## 🚀 `PROMO` [Spring Boost Campaign](https://appseed.us/discounts/) `50%OFF`
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+> The **discount is applicable to all products and licenses** (no stock limits) until `15.MAR`
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+[![Spring Boost Campaign](https://user-images.githubusercontent.com/51070104/221118889-171c5afc-4d01-402b-8681-61b37338e26c.png)](https://appseed.us/discounts/)
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+<br />
+
 > Features:
 
 - ✅ `Up-to-date dependencies`