MINOR: [C#] Bump xunit from 2.8.1 to 2.9.0 in /csharp (apache#43259)

Bumps xunit from 2.8.1 to 2.9.0.

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Authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Signed-off-by: Curt Hagenlocher <[email protected]>

Author: dependabot[bot]

csharp/test/Apache.Arrow.Compression.Tests/Apache.Arrow.Compression.Tests.csproj

@@ -8,7 +8,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.10.0" />
-    <PackageReference Include="xunit" Version="2.8.1" />
+    <PackageReference Include="xunit" Version="2.9.0" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.8.2" />
   </ItemGroup>
 

csharp/test/Apache.Arrow.Flight.Sql.Tests/Apache.Arrow.Flight.Sql.Tests.csproj

@@ -7,7 +7,7 @@
 
     <ItemGroup>
       <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.10.0" />
-      <PackageReference Include="xunit" Version="2.8.1" />
+      <PackageReference Include="xunit" Version="2.9.0" />
       <PackageReference Include="xunit.runner.visualstudio" Version="2.8.2" />
       <PackageReference Include="coverlet.collector" Version="6.0.2" />
     </ItemGroup>

csharp/test/Apache.Arrow.Flight.Tests/Apache.Arrow.Flight.Tests.csproj

@@ -7,7 +7,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.10.0" />
-    <PackageReference Include="xunit" Version="2.8.1" />
+    <PackageReference Include="xunit" Version="2.9.0" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.8.2" />
     <PackageReference Include="coverlet.collector" Version="6.0.2" />
   </ItemGroup>

csharp/test/Apache.Arrow.Tests/Apache.Arrow.Tests.csproj

@@ -17,7 +17,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.10.0" />
-    <PackageReference Include="xunit" Version="2.8.1" />
+    <PackageReference Include="xunit" Version="2.9.0" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.8.2">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers</IncludeAssets>