code: public void deleteDeployKey(Object projectIdOrPath, Integer keyId) throws GitLabApiException {
  
          if (keyId == null) {
              throw new RuntimeException("keyId cannot be null");
          }
  
          delete(Response.Status.OK, null, "projects", getProjectIdOrPath(projectIdOrPath), "deploy_keys", keyId);
      }
docs: Removes a deploy key from the project. If the deploy key is used only for this project,it will be deleted from the system.
  
  <pre><code>GitLab Endpoint: DELETE /projects/:id/deploy_keys/:key_id</code></pre>
  
  @param projectIdOrPath the project in the form of an Integer(ID), String(path), or Project instance
  @param keyId the ID of the deploy key to delete
  @throws GitLabApiException if any exception occurs