Update dependencies to latest patch version (#771)

Author: adityapatwardhan

src/Microsoft.PowerShell.PlatyPS.csproj

@@ -16,9 +16,9 @@
 
   <ItemGroup>
     <PackageReference Include="Markdig.Signed" Version="[0.33]" />
-    <PackageReference Include="PowerShellStandard.Library" Version="5.1.0" PrivateAssets="All" />
+    <PackageReference Include="PowerShellStandard.Library" Version="5.1.1" PrivateAssets="All" />
     <PackageReference Include="Microsoft.CSharp" Version="4.7.0" />
-    <PackageReference Include="YamlDotNet" Version="15.1.2" />
+    <PackageReference Include="YamlDotNet" Version="15.1.6" />
   </ItemGroup>
 
   <ItemGroup>