Bump Amazon.Lambda.Core from 2.8.0 to 2.8.1

---
updated-dependencies:
- dependency-name: Amazon.Lambda.Core
  dependency-version: 2.8.1
  dependency-type: direct:production
  update-type: version-update:semver-patch
- dependency-name: Amazon.Lambda.Core
  dependency-version: 2.8.1
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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Author: dependabot[bot]

test/SimpleAPI.Tests/SimpleAPI.Tests.csproj

@@ -16,7 +16,7 @@
     </Content>
   </ItemGroup>
   <ItemGroup>
-    <PackageReference Include="Amazon.Lambda.Core" Version="2.8.0" />
+    <PackageReference Include="Amazon.Lambda.Core" Version="2.8.1" />
     <PackageReference Include="Amazon.Lambda.TestUtilities" Version="3.0.1" />
     <PackageReference Include="Amazon.Lambda.APIGatewayEvents" Version="2.7.3" />
     <PackageReference Include="AWSSDK.Extensions.NETCore.Setup" Version="4.0.3.22" />