fix(cta-section): ensure buttons are not allowed as cta types (#7782)

### Related Ticket(s)
#7439

### Description
Currently the CTA Section story allowed Buttons as CTA types for the content items. With this new PR, I removed the ability to choose Buttons from the knob, as well as ensure that any slotted Button Group does not render if within a `cta-block-item` element.

### Changelog

**New**

- `ButtonGroup` will not rendered if used inside a `cta-block-item` element

**Removed**
- buttons option in CTA type knob for `CTASection`

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packages/web-components/src/components/cta-block/cta-block-item.ts

@@ -60,6 +60,7 @@ class DDSCTABlockItem extends StableSelectorMixin(DDSContentItem) {
     const { name } = target as HTMLSlotElement;
     const hasContent = (target as HTMLSlotElement)
       .assignedNodes()
+      .filter(elem => !(elem as HTMLElement).matches?.((this.constructor as typeof DDSCTABlockItem).selectorButtonGroup))
       .some(node => node.nodeType !== Node.TEXT_NODE || node!.textContent!.trim());
     this[slotExistencePropertyNames[name] || '_hasStatistic'] = hasContent;
   }

packages/web-components/src/components/cta-section/__stories__/cta-section.stories.react.tsx

@@ -25,8 +25,6 @@ import DDSCTABlockItemRow from '@carbon/ibmdotcom-web-components/es/components-r
 import DDSCTABlockItem from '@carbon/ibmdotcom-web-components/es/components-react/cta-block/cta-block-item';
 import DDSContentItemHeading from '@carbon/ibmdotcom-web-components/es/components-react/content-item/content-item-heading';
 import DDSContentItemCopy from '@carbon/ibmdotcom-web-components/es/components-react/content-item/content-item-copy';
-import DDSButtonGroup from '@carbon/ibmdotcom-web-components/es/components-react/button-group/button-group';
-import DDSButtonCTA from '@carbon/ibmdotcom-web-components/es/components-react/cta/button-cta';
 import Desktop from '@carbon/pictograms-react/es/desktop/index.js';
 import DDSVideoPlayerContainer from '@carbon/ibmdotcom-web-components/es/components-react/video-player/video-player-container';
 import DDSLinkList from '@carbon/ibmdotcom-web-components/es/components-react/link-list/link-list';
@@ -49,16 +47,6 @@ const contentItemTypeMap = {
       ))}
     </DDSCTABlockItem>
   ),
-  button: ({ heading, copy }) => (
-    <DDSCTABlockItem>
-      <DDSContentItemHeading>{heading}</DDSContentItemHeading>
-      <DDSContentItemCopy>{copy}</DDSContentItemCopy>
-      <DDSButtonGroup slot="footer">
-        <DDSButtonCTA>Button 1</DDSButtonCTA>
-        <DDSButtonCTA>Button 2</DDSButtonCTA>
-      </DDSButtonGroup>
-    </DDSCTABlockItem>
-  ),
   statistics: ({ heading, copy, links }) => (
     <DDSCTABlockItem>
       <span slot="statistics">10%</span>
@@ -115,7 +103,6 @@ const renderItems = (item, count) => {
 
 const contentItemTypeOptions = {
   Text: 'text',
-  Button: 'button',
   Statistics: 'statistics',
   Pictogram: 'pictogram',
   Media: 'media',

packages/web-components/src/components/cta-section/__stories__/cta-section.stories.ts

@@ -33,16 +33,6 @@ const contentItemTypeMap = {
       )}
     </dds-cta-block-item>
   `,
-  button: ({ heading, copy }) => html`
-    <dds-cta-block-item>
-      <dds-content-item-heading>${heading}</dds-content-item-heading>
-      <dds-content-item-copy>${copy}</dds-content-item-copy>
-      <dds-button-group slot="footer">
-        <dds-button-cta>Button 1</dds-button-cta>
-        <dds-button-cta>Button 2</dds-button-cta>
-      </dds-button-group>
-    </dds-cta-block-item>
-  `,
   statistics: ({ heading, copy, links }) => html`
     <dds-cta-block-item>
       <span slot="statistics">10%</span>
@@ -109,7 +99,6 @@ const contentItemTypeMap = {
 
 const contentItemTypeOptions = {
   Text: 'text',
-  Button: 'button',
   Statistics: 'statistics',
   Pictogram: 'pictogram',
   Media: 'media',