README.md in dry-schema-1.5.5 vs README.md in dry-schema-1.5.6

- old
+ new

@@ -19,10 +19,10 @@
 
 ## Supported Ruby versions
 
 This library officially supports the following Ruby versions:
 
-* MRI >= `2.4`
+* MRI >= `2.5
 * jruby >= `9.2`
 
 ## License
 
 See `LICENSE` file.