docs: public Variable createVariable(Object groupIdOrPath, String key, String value, Boolean isProtected) throws GitLabApiException {
  
          GitLabApiForm formData = new GitLabApiForm()
                  .withParam("key", key, true)
                  .withParam("value", value, true)
                  .withParam("protected", isProtected);
          Response response = post(Response.Status.CREATED, formData, "groups", getGroupIdOrPath(groupIdOrPath), "variables");
          return (response.readEntity(Variable.class));
      }