Switch to the modern docfx template (#358)

Author: roji

conceptual/Npgsql/index.md

@@ -1,16 +1,11 @@
----
-layout: doc
-title: Documentation
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+# Getting Started
 
 [![stable](https://img.shields.io/nuget/v/Npgsql.svg?label=stable)](https://www.nuget.org/packages/Npgsql/)
 [![next patch](https://img.shields.io/myget/npgsql/v/npgsql.svg?label=next%20patch)](https://www.myget.org/feed/npgsql/package/nuget/Npgsql)
 [![vnext](https://img.shields.io/myget/npgsql-vnext/v/npgsql.svg?label=vnext)](https://www.myget.org/feed/npgsql-vnext/package/nuget/Npgsql)
 [![build](https://img.shields.io/github/actions/workflow/status/npgsql/npgsql/build.yml?branch=main)](https://github.com/npgsql/npgsql/actions)
 [![gitter](https://img.shields.io/badge/gitter-join%20chat-brightgreen.svg)](https://gitter.im/npgsql/npgsql)
 
-## Getting Started
-
 The best way to use Npgsql is to install its [nuget package](https://www.nuget.org/packages/Npgsql/).
 
 Npgsql aims to be fully ADO.NET-compatible, its API should feel almost identical to other .NET database drivers.

conceptual/Npgsql/installation.md

@@ -1,7 +1,4 @@
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-layout: doc
-title: Installation
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+# Installation
 
 ## Offical Packages
 

docfx.json

@@ -30,7 +30,7 @@
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-        "template"
+        "modern"
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