Update the compatibility matrix

Author: igalshilman

README.md

@@ -29,7 +29,7 @@ The Python SDK is currently in active development, and might break across releas
 
 The compatibility with Restate is described in the following table:
 
-| Restate Server\sdk-python | 0.0/0.1/0.2 | 0.3 |
+| Restate Server\sdk-python | 0.0/0.1/0.2 | 0.3/0.4 |
 |---------------------------|-------------|-----|
 | 1.0                       | ✅           | ❌   |
 | 1.1                       | ✅           | ✅   |