build(deps): bump Azure.Security.KeyVault.Keys

Bumps [Azure.Security.KeyVault.Keys](https://github.com/Azure/azure-sdk-for-net) from 4.6.0 to 4.7.0.
- [Release notes](https://github.com/Azure/azure-sdk-for-net/releases)
- [Commits](Azure/azure-sdk-for-net@Azure.Security.KeyVault.Keys_4.6.0...Azure.Security.KeyVault.Keys_4.7.0)

---
updated-dependencies:
- dependency-name: Azure.Security.KeyVault.Keys
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

Notation.Plugin.AzureKeyVault/Notation.Plugin.AzureKeyVault.csproj

@@ -19,7 +19,7 @@
   <ItemGroup>
     <PackageReference Include="Azure.Identity" Version="1.13.1" />
     <PackageReference Include="Azure.Security.KeyVault.Certificates" Version="4.6.0" />
-    <PackageReference Include="Azure.Security.KeyVault.Keys" Version="4.6.0" />
+    <PackageReference Include="Azure.Security.KeyVault.Keys" Version="4.7.0" />
     <PackageReference Include="Azure.Security.KeyVault.Secrets" Version="4.7.0" />
     <PackageReference Include="System.Security.Cryptography.Pkcs" Version="8.0.0" />
   </ItemGroup>