.Net: Set baseline to 1.6.2 (#5473)

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---------

Co-authored-by: Roger Barreto <19890735+RogerBarreto@users.noreply.github.com>
Co-authored-by: Dmytro Struk <13853051+dmytrostruk@users.noreply.github.com>

dotnet/nuget/nuget-package.props

@@ -10,7 +10,7 @@
     <IsPackable>true</IsPackable>
 
     <!-- Package validation. Baseline Version should be lower than current version. -->
-    <PackageValidationBaselineVersion>1.5.0</PackageValidationBaselineVersion>
+    <PackageValidationBaselineVersion>1.6.2</PackageValidationBaselineVersion>
     <!-- Validate assembly attributes only for Publish builds -->
     <NoWarn Condition="'$(Configuration)' != 'Publish'">$(NoWarn);CP0003</NoWarn>
     <!-- Do not validate reference assemblies -->