tech debt: review/assess ajax `request.fail` on NApps handlers too

[viniarck]

Related to #60, we have many request.fail ajax handling there too, not all of them are susceptible to what was found on issue 60, but let's reassess/review if they might be accessing a property undefined in case a connection is lost:

❯ rg --follow 'fail' -g "*.kytos"
napps/amlight/sdntrace/ui/k-info-panel/show_trace_results.kytos
102:      request.fail(function(data) {

napps/kytos/maintenance/ui/k-info-panel/list_maintenance.kytos
123:        request.fail(function(jqXHR, status) {
124:            alert("Request failed: " + status + ".")
131:        Displays maintenance windows regardless of success or failure.
146:        request.fail(function(jqXHR, status) {
147:            // If failure, display the maintenance windows without topology.

napps/amlight/sdntrace/ui/k-toolbar/main.kytos
129:             self.failNotification(data);
138:       request.fail(function(data) {
149:    failNotification(data){  
175:      request.fail(function(data) {

napps/kytos/maintenance/ui/k-info-panel/edit_window.kytos
192:                request.fail(function(jqXHR, status, error ) {
201:                        title: 'Updated Window failed.',
204:                    // Notify on failure.
247:                request.fail(function(jqXHR, status) {
252:                    // Notify on failure.
350:                request.fail(function( jqXHR, status ) {
355:                    // Notify failure.
410:                request.fail(function(jqXHR, status) {
415:                    // Notify failure.
452:                request.fail(function(jqXHR, status) {
457:                    // Notify failure.
494:                request.fail(function(jqXHR, status) {
499:                    // Notify failure
602:                request.fail(function(jqXHR, status) {
611:                        title: 'Finish Window failed.',
614:                    // Notify on failure.
643:                request.fail(function(jqXHR, status) {
652:                        title: 'Extending Window failed.',
655:                    // Notify on failure.

napps/kytos/maintenance/ui/k-toolbar/main.kytos
138:                request.fail(function(jqXHR, status, error) {
197:              request.fail(function( jqXHR, textStatus ) {
198:                  alert("Request failed: " + textStatus);
225:               request.fail(function( jqXHR, textStatus) {
226:                   alert("Request failed: " + textStatus)

napps/amlight/sdntrace_cp/ui/k-toolbar/main.kytos
148:      request.fail(function(data) {

napps/kytos/mef_eline/ui/k-info-panel/list_connections.kytos
187:      request.fail(function( jqXHR, textStatus ) {
188:        alert( "Request failed: " + textStatus );
224:      request.fail(function( jqXHR, textStatus ) {
225:        alert( "Request failed: " + textStatus );

napps/kytos/mef_eline/ui/k-info-panel/show_circuit.kytos
414:      request.fail(function( jqXHR, textStatus ) {
417:            description: "Request failed: " + textStatus
437:      request.fail(function( jqXHR, textStatus ) {
440:            description: "Request failed: " + textStatus
638:      request.fail(function( jqXHR, textStatus ) {
641:          description: "Request failed: " + textStatus
777:      request.fail(function(data) {
779:          title: 'Redeploy EVC failed',
894:      request.fail(function(data) {
896:          title: 'Update EVC failed',

napps/kytos/mef_eline/ui/k-toolbar/main.kytos
552:        circuit_request.fail(this.post_error);

napps/kytos/pathfinder/ui/k-toolbar/main.kytos
205:      request.fail(function(data) {

napps/kytos/topology/ui/k-info-panel/link_info.kytos
131:     msg_state_failure(data){
147:       request.fail(this.msg_state_failure)
175:       request.fail(function(data) {
204:       request.fail(function(data) {
240:       request.fail(function(data) {

napps/kytos/topology/ui/k-info-panel/switch_info.kytos
176:     get_links_failure(data){
191:       request.fail(this.get_links_failure)
229:       request.fail(function(data) {
256:       request.fail(function(data) {
299:     msg_state_failure(data){
314:       request.fail(this.msg_state_failure)
335:       request.fail(function(data){
369:       request.fail(function(data) {