Add Boards::UpdateService service to update boards

app/services/boards/update_service.rb

+module Boards
+  class UpdateService < Boards::BaseService
+    def execute(board)
+      board.update(name: params[:name])
+    end
+  end
+end

spec/services/boards/update_service_spec.rb

+require 'spec_helper'
+
+describe Boards::UpdateService, services: true do
+  describe '#execute' do
+    let(:project) { create(:empty_project) }
+    let!(:board)  { create(:board, project: project, name: 'Backend') }
+
+    it "updates board's name" do
+      service = described_class.new(project, double, name: 'Engineering')
+
+      service.execute(board)
+
+      expect(board).to have_attributes(name: 'Engineering')
+    end
+
+    it 'returns true with valid params' do
+      service = described_class.new(project, double, name: 'Engineering')
+
+      expect(service.execute(board)).to eq true
+    end
+
+    it 'returns false with invalid params' do
+      service = described_class.new(project, double, name: nil)
+
+      expect(service.execute(board)).to eq false
+    end
+  end
+end