chore: bump scalingo provider version from ~> 2.2 to ~> 2.7 (#16)

Required to access new features: project_id, hds_resource,
letsencrypt_enabled, limited collaborators, and base_url output.

Author: josephpage

versions.tf

@@ -4,7 +4,7 @@ terraform {
   required_providers {
     scalingo = {
       source  = "scalingo/scalingo"
-      version = "~> 2.2"
+      version = "~> 2.7"
     }
 
     environment = {