Update supported go versions to 1.20 and 1.21
diff --git a/lib/go/test/fuzz/go.mod b/lib/go/test/fuzz/go.mod
index 6641881..41cccc3 100644
--- a/lib/go/test/fuzz/go.mod
+++ b/lib/go/test/fuzz/go.mod
@@ -1,6 +1,6 @@
 module github.com/apache/thrift/lib/go/test/fuzz
 
-go 1.19
+go 1.20
 
 replace github.com/apache/thrift => ../../../../