Added - Upgrade golang version to 1.20.7

Author: jiaqchenO

.go-version

@@ -1,2 +1 @@
-1.18.8
-
+1.20.7

README.md

@@ -15,7 +15,7 @@
 ## Requirements
 
 - [Terraform](https://www.terraform.io/downloads.html) v0.12.31 or greater
-- [Go](https://golang.org/doc/install) 1.18.8 (recommended)
+- [Go](https://golang.org/doc/install) 1.20.7 (recommended)
 
 
 ## Building the Provider

go.mod

@@ -78,4 +78,4 @@ require (
 // Uncomment this line to get OCI Go SDK from local source instead of github
 replace github.com/oracle/oci-go-sdk/v65 v65.49.0 => ./vendor/github.com/oracle/oci-go-sdk
 
-go 1.18
+go 1.20