feat: migrate emphasis (#12963)

| 📖 [PR App][pr] | 🎫 Resolve CX-1135, RM-11085 |
| :-------------: | :-----------------: |

## 🧰 Changes

Fixes incompatable emphasis during the migration.

I [fixed this](#988) in
`@readme/mdx`, but I think it'll be nicer to keep the migration specific
stuff in the main app.

## 💁 Customer Impact

<!-- PLEASE DESCRIBE IF THIS CHANGE AFFECTS CUSTOMERS AND HOW -->
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## 🧬 QA & Testing

- [ ] insert the string `*the recommended initial action is to**initiate
a[reversal operation
(rollback)](https://docs.jupico.com/reference/ccrollback)**. *` into a
page
- [ ] note the bold and italics
- [ ] migrate the project
- [ ] confirm that the bold and italics render the same in the dash and
hub

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[next]: https://next.readme.ninja
[pr]: https://readme-pr-12963.readme.ninja
[ui]: https://readme-pr-12963.readme.ninja/ui

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emphasis.test.ts

@@ -0,0 +1,36 @@
+import * as rmdx from '@readme/mdx';
+
+import { compatParser as mdast } from '@readme/backend/models/project/lib/migrateMdx/compatParser';
+
+describe('migrating emphasis', () => {
+  it('trims whitespace surrounding phrasing content (emphasis, strong, etc)', () => {
+    const md = '** bold ** and _ italic _ and ***   bold italic ***';
+
+    const mdx = rmdx.mdx(mdast(md));
+    expect(mdx).toMatchInlineSnapshot(`
+      "**bold** and *italic* and ***bold italic***
+      "
+    `);
+  });
+
+  it('moves whitespace surrounding phrasing content (emphasis, strong, etc) to the appropriate place', () => {
+    const md = '**bold **and also_ italic_ and*** bold italic***aaaaaah';
+
+    const mdx = rmdx.mdx(mdast(md));
+    expect(mdx).toMatchInlineSnapshot(`
+      "**bold** and also *italic* and ***bold italic***aaaaaah
+      "
+    `);
+  });
+
+  it('migrates a complex case', () => {
+    const md =
+      '*the recommended initial action is to**initiate a[reversal operation (rollback)](https://docs.jupico.com/reference/ccrollback)**. *';
+
+    const mdx = rmdx.mdx(mdast(md));
+    expect(mdx).toMatchInlineSnapshot(`
+      "*the recommended initial action is to**initiate a[reversal operation (rollback)](https://docs.jupico.com/reference/ccrollback)**.*
+      "
+    `);
+  });
+});

tables.test.ts

@@ -1,6 +1,6 @@
 import * as rmdx from '@readme/mdx';
 
-import { rdmdCompatParser as mdast } from '@readme/backend/models/project/lib/migrateMdx/rdmdCompatParser';
+import { compatParser as mdast } from '@readme/backend/models/project/lib/migrateMdx/compatParser';
 
 describe('mdx migration of tables', () => {
   it('compiles tables with newlines and inline code', () => {