fix: update supported RN version to 0.64 (#1912)

Based on WoLewicki/libs-rn-version-tester/actions/runs/3410971949/jobs/5674595317 it seems that react-native-svg does not work for projects with RN < 0.64.

README.md

@@ -74,7 +74,7 @@ expo install react-native-svg
 | >=7              | >=0.57.4     |
 | >=8              | >=0.57.4     |
 | >=9              | >=0.57.4     |
-| >=12.3.0         | >=0.63.0     |
+| >=12.3.0         | >=0.64.0     |
 
 ## Support for Fabric