Added the versioning for Revocation mode functionality

Author: anangaur

docs/reference/errors-and-warnings/NU3028.md

@@ -22,7 +22,7 @@ Certificate chain building failed for the timestamp signature. The timestamp sig
 ### Solution
 Use a trusted and valid certificate. Check internet connectivity.gits
 
-### Revocation check mode
+### Revocation check mode *(4.8.1+)*
 If the machine has restricted internet access (such as a build machine in a CI/CD scenario), installing/restoring a signed nuget package will result in this warning since the revocation servers are not reachable. This is expected.
 However, in some cases, this may have unintended concequences such as the package install/restore taking longer than usual. If that happens, you can work around it by setting the `NUGET_CERT_REVOCATION_MODE` environment variable to `offline`. This will force NuGet to check the revocation status of the certificate only against the cached certificate revocation list, and NuGet will not attempt to reach revocation servers.