fix: open .NET link in new tab

src/Blog/Components/Layout/Header.razor

@@ -4,8 +4,8 @@
   <div class="title-container">
     <NavLink href="/">
       <h1>journal</h1>
-      <p>using 
-        <a href="https://dotnet.microsoft.com/">
+      <p>using
+        <a target="_blank" href="https://dotnet.microsoft.com/">
           .NET @Environment.Version.Major
         </a>
       </p>
@@ -18,4 +18,4 @@
       <span class="sr-only">Stevan Freeborn</span>
     </a>
   </div>
-</header>
+</header>