[localization] Fix template names in Japanese localization for .NET MAUI ContentPage and Window (#25858)

src/Templates/src/templates/maui-contentpage-csharp/.template.config/localize/templatestrings.ja.json

@@ -1,6 +1,6 @@
 {
   "author": "Microsoft",
-  "name": "..NET MAUI ContentPage (C#)",
+  "name": ".NET MAUI ContentPage (C#)",
   "description": "A page for displaying content using C#.",
   "postActions/openInEditor/description": "エディターで NewPage1.cs を開きます。",
   "symbols/namespace/description": "生成されたコードの名前空間。"

src/Templates/src/templates/maui-window-csharp/.template.config/localize/templatestrings.ja.json

@@ -1,6 +1,6 @@
 {
   "author": "Microsoft",
-  "name": "..NET MAUI Window (C#)",
+  "name": ".NET MAUI Window (C#)",
   "description": "A window for displaying a page using C#.",
   "postActions/openInEditor/description": "エディターで NewWindow1.cs を開きます。",
   "symbols/namespace/description": "生成されたコードの名前空間。"