[eslint-plugin-azure-sdk] Update Markdown plugin (#29099)

### Packages impacted by this PR

- @azure/eslint-plugin-azure-sdk

### Issues associated with this PR

- #28861

### Describe the problem that is addressed by this PR

Updates to latest plugin version.

### What are the possible designs available to address the problem? If
there are more than one possible design, why was the one in this PR
chosen?


### Are there test cases added in this PR? _(If not, why?)_


### Provide a list of related PRs _(if any)_


### Command used to generate this PR:**_(Applicable only to SDK release
request PRs)_

### Checklists
- [x] Added impacted package name to the issue description
- [ ] Does this PR needs any fixes in the SDK Generator?** _(If so,
create an Issue in the
[Autorest/typescript](https://github.com/Azure/autorest.typescript)
repository and link it here)_
- [ ] Added a changelog (if necessary)

common/tools/eslint-plugin-azure-sdk-helper/package.json

@@ -12,7 +12,7 @@
     "eslint-plugin-no-only-tests": "^3.0.0",
     "eslint-plugin-promise": "^6.0.0",
     "eslint-plugin-tsdoc": "^0.2.10",
-    "eslint-plugin-markdown": "~3.0.0"
+    "eslint-plugin-markdown": "^4.0.0"
   },
   "dependencies": {
     "@typescript-eslint/experimental-utils": "~5.57.0",

common/tools/eslint-plugin-azure-sdk/package.json

@@ -89,7 +89,7 @@
     "@vitest/coverage-istanbul": "^1.4.0",
     "cross-env": "^7.0.3",
     "eslint": "^8.50.0",
-    "eslint-plugin-markdown": "~3.0.0",
+    "eslint-plugin-markdown": "^4.0.0",
     "prettier": "^3.2.5",
     "rimraf": "^5.0.5",
     "source-map-support": "^0.5.9",

common/tools/eslint-plugin-azure-sdk/src/configs/azure-sdk-base.ts

@@ -141,7 +141,7 @@ export default {
     },
     {
       files: ["**/*.md/*.{js,javascript}"],
-      extends: ["plugin:markdown/recommended"],
+      extends: ["plugin:markdown/recommended-legacy"],
       rules: {
         "no-restricted-imports": [
           "error",