Update environment_version and dbr_version

Author: gkiko

libs/template/templates/default-scala/library/template_variables.tmpl

@@ -8,7 +8,7 @@
 {{- end }}
 
 {{ define `dbr_version` -}}
-    17.0
+    17.3
 {{- end }}
 
 {{ define `scala_major_minor_version` -}}

libs/template/templates/default-scala/template/{{.project_name}}/resources/{{.project_name}}.job.yml.tmpl

@@ -31,7 +31,7 @@ resources:
       environments:
         - environment_key: default
           spec:
-            environment_version: "4-scala-preview"
+            environment_version: "4"
             java_dependencies:
               - ${workspace.artifact_path}/.internal/{{.project_name}}-assembly-{{template `version` .}}.jar
 {{- else}}