fix slack notification processor attachment blocks

A `section` block requires that either a `text` or `fields` item be
included. Since we were already defaulting the payload.description, this
change simply ensures that the text portion of the block is specified
(with tests updated accordingly).

Signed-off-by: Brian Phillips <28457+brianphillips@users.noreply.github.com>

.changeset/crazy-chefs-sin.md

@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-notifications-backend-module-slack': patch
+---
+
+Fix slack notification processor to handle a notification with an empty description

plugins/notifications-backend-module-slack/src/lib/SlackNotificationProcessor.test.ts

@@ -158,6 +158,10 @@ describe('SlackNotificationProcessor', () => {
           blocks: [
             {
               type: 'section',
+              text: {
+                text: 'No description provided',
+                type: 'mrkdwn',
+              },
               accessory: {
                 type: 'button',
                 text: {
@@ -229,6 +233,10 @@ describe('SlackNotificationProcessor', () => {
             blocks: [
               {
                 type: 'section',
+                text: {
+                  text: 'No description provided',
+                  type: 'mrkdwn',
+                },
                 accessory: {
                   type: 'button',
                   text: {

plugins/notifications-backend-module-slack/src/lib/util.ts

@@ -46,12 +46,10 @@ export function toSlackBlockKit(payload: NotificationPayload): KnownBlock[] {
   return [
     {
       type: 'section',
-      ...(description && {
-        text: {
-          type: 'mrkdwn',
-          text: description ?? 'No description provided',
-        },
-      }),
+      text: {
+        type: 'mrkdwn',
+        text: description ?? 'No description provided',
+      },
       accessory: {
         type: 'button',
         text: {