Add PDF to infer mime type list (#1298)

Enables static PDF files to be returned. 

## What problem is it solving?

It will allow the download of static PDF files.

## How is the problem addressed?

By adding PDF to the infer mime type list. 

## Testing Instructions

- Check out this branch
- [Open Playground
](http://127.0.0.1:5400/website-server/?url=/wp-admin/upload.php)
- Upload a PDF as media
- Right click on Download file an open the link in a new tab
- See that the PDF loads

---------

Co-authored-by: Adam Zielinski <adam@adamziel.com>

packages/php-wasm/universal/src/lib/php-request-handler.ts

@@ -352,6 +352,38 @@ function inferMimeType(path: string): string {
 		case 'txt':
 		case 'md':
 			return 'text/plain';
+		case 'pdf':
+			return 'application/pdf';
+		case 'webp':
+			return 'image/webp';
+		case 'mp3':
+			return 'audio/mpeg';
+		case 'mp4':
+			return 'video/mp4';
+		case 'csv':
+			return 'text/csv';
+		case 'xls':
+			return 'application/vnd.ms-excel';
+		case 'xlsx':
+			return 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet';
+		case 'doc':
+			return 'application/msword';
+		case 'docx':
+			return 'application/vnd.openxmlformats-officedocument.wordprocessingml.document';
+		case 'ppt':
+			return 'application/vnd.ms-powerpoint';
+		case 'pptx':
+			return 'application/vnd.openxmlformats-officedocument.presentationml.presentation';
+		case 'zip':
+			return 'application/zip';
+		case 'rar':
+			return 'application/x-rar-compressed';
+		case 'tar':
+			return 'application/x-tar';
+		case 'gz':
+			return 'application/gzip';
+		case '7z':
+			return 'application/x-7z-compressed';
 		default:
 			return 'application-octet-stream';
 	}