Bump Polyfill from 2.4.0 to 2.6.0 in /src

Bumps [Polyfill](https://github.com/SimonCropp/Polyfill) from 2.4.0 to 2.6.0.
- [Commits](https://github.com/SimonCropp/Polyfill/commits)

---
updated-dependencies:
- dependency-name: Polyfill
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

src/TextCopy/TextCopy.csproj

@@ -10,7 +10,7 @@
     <DefineConstants>$(DefineConstants);IOS</DefineConstants>
   </PropertyGroup>
   <ItemGroup>
-    <PackageReference Include="Polyfill" Version="2.4.0" PrivateAssets="all" />
+    <PackageReference Include="Polyfill" Version="2.6.0" PrivateAssets="all" />
     <PackageReference Include="System.Runtime.InteropServices.RuntimeInformation" Version="4.3.0" Condition="$(TargetFramework) == 'net462'" />
     <WeaverFiles Include="$(SolutionDir)Weavers\bin\$(Configuration)\netstandard2.0\Weavers.dll" />
     <PackageReference Include="Fody" Version="6.8.0" PrivateAssets="all" />