Use VBA product-level header

This content needs to use a VBA product-level header; this PR adds that header to this docset.
Please note: I have drafted a VBA header on your behalf, which can be reviewed here https://github.com/MicrosoftDocs/DocsRoot/blob/main/content-nav/MSDocsHeader-VBA.yml. Feel free to propose any changes to the header by opening a PR on that file. Headers should be iterated over time to reflect user and content needs, so frequent updates are encouraged. Here are the guidelines for L2 headers: https://review.learn.microsoft.com/en-us/help/platform/navigation-product-level-header-overview?branch=main

Author: raprice

docfx.json

@@ -36,7 +36,7 @@
     "overwrite": [],
     "externalReference": [],
     "globalMetadata": {
-      "uhfHeaderId": "MSDocsHeader-Dev_Office",
+      "uhfHeaderId": "MSDocsHeader-VBA",
       "breadcrumb_path": "/breadcrumb/toc.json",
       "extendBreadcrumb": true,
       "ms.suite": "office",