Renamed spec file to be consistent

spec/requests/api/graphql/mutations/ci/cancel_pipeline_spec.rb

-# frozen_string_literal: true
-
-require 'spec_helper'
-
-RSpec.describe 'PipelineCancel' do
-  include GraphqlHelpers
-
-  let(:user) { create(:user) }
-  let(:project) { create(:project) }
-  let(:pipeline) { create(:ci_pipeline,  project: project, user: user) }
-
-  let(:mutation) do
-    variables = {
-      id: pipeline.id
-    }
-    graphql_mutation(:pipeline_retry, variables,
-                     <<-QL
-                       errors
-                       pipeline {
-                         id
-                       }
-                     QL
-    )
-  end
-
-  let(:mutation_response) { graphql_mutation_response(:pipeline_cancel) }
-
-  before do
-    project.add_maintainer(user)
-  end
-
-  it 'returns an error if the user is not allowed to retry the pipeline' do
-    post_graphql_mutation(mutation, current_user: create(:user))
-
-    expect(graphql_errors).not_to be_empty
-  end
-
-  it 'retries a pipeline' do
-    post_graphql_mutation(mutation, current_user: user)
-
-    expect(response).to have_gitlab_http_status(:success)
-    expect(mutation_response['pipeline']['id']).to include(pipeline.id.to_s)
-  end
-end
-