[fix][pwa] Add missing form factor in web manifest screenshots (#56)

Added missing form factor in PWA's web manifest screenshots.

Author: AlexJSully

src/icon/site.webmanifest

@@ -126,20 +126,23 @@
 			"sizes": "1600x1089",
 			"type": "image/webp",
 			"platform": "wide",
+			"form_factor": "wide",
 			"label": "Landing Page"
 		},
 		{
 			"src": "./screenshot2.webp",
 			"sizes": "1600x1032",
 			"type": "image/webp",
 			"platform": "wide",
+			"form_factor": "wide",
 			"label": "Example article with Caravaneer 2 interview"
 		},
 		{
 			"src": "./screenshot3.webp",
 			"sizes": "1600x1089",
 			"type": "image/webp",
 			"platform": "wide",
+			"form_factor": "wide",
 			"label": "Archive of articles from Small Dev Talk"
 		}
 	],