Fix go.mod

Partially revert 32bd0bd950739ca048d10783a7617e317c8b9419.
diff --git a/go.mod b/go.mod
index 86ded1f..2d3d1c6 100644
--- a/go.mod
+++ b/go.mod
@@ -1,5 +1,5 @@
 module github.com/apache/thrift
 
-go 1.19.2
+go 1.18
 
 require github.com/golang/mock v1.5.0