Reapply 5.1.0 breaking change, will be released as 6.0

This reverts commit 1157727.

Author: khellang

src/Scrutor/Scrutor.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <Description>Register services using assembly scanning and a fluent API.</Description>
-    <VersionPrefix>5.1.2</VersionPrefix>
+    <VersionPrefix>5.1.1</VersionPrefix>
     <Authors>Kristian Hellang</Authors>
     <TargetFrameworks>net462;netstandard2.0;net8.0</TargetFrameworks>
     <NoWarn>$(NoWarn);CS1591</NoWarn>