fix(nx-dev): fix markdoc table data alignment (#28274)

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## Current Behavior
<!-- This is the behavior we have today -->

Currently, our table heading generated from markdown files `.md` are
positioned `center` while the data `td` are positioned `left`.

It doesn't look uniform and on larger tables, it can be jarring.

Examples: 
- https://nx.dev/ci/reference/release-notes#helm-package-compatibility
- https://nx.dev/reference/releases#supported-versions
-
https://nx.dev/blog/reliable-ci-a-new-execution-model-fixing-both-flakiness-and-slowness#problem-in-numbers

## Expected Behavior
<!-- This is the behavior we should expect with the changes in this PR
-->
Both heading and data should have the same alignment to be symmetrical. 

## Related Issue(s)
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merged. -->

Fixes #

nx-dev/ui-markdoc/src/index.ts

@@ -56,7 +56,7 @@ import { pill } from './lib/tags/pill.schema';
 import { fence } from './lib/nodes/fence.schema';
 import { FenceWrapper } from './lib/nodes/fence-wrapper.component';
 import { VideoPlayer, videoPlayer } from './lib/tags/video-player.component';
-
+import { td } from './lib/nodes/td.schema';
 // TODO fix this export
 export { GithubRepository } from './lib/tags/github-repository.component';
 
@@ -70,6 +70,7 @@ export const getMarkdocCustomConfig = (
       heading: getHeadingSchema(headingClass),
       image: getImageSchema(documentFilePath),
       link,
+      td,
     },
     tags: {
       callout,

nx-dev/ui-markdoc/src/lib/nodes/td.schema.ts

@@ -0,0 +1,8 @@
+import { Schema } from '@markdoc/markdoc';
+
+export const td: Schema = {
+  render: 'td',
+  attributes: {
+    className: { type: 'String', default: 'text-center' },
+  },
+};