update README.md file with new signing information

Signed-off-by: Vadim Rozenfeld <[email protected]>

README.md

@@ -23,11 +23,11 @@ The `stable` builds of virtio-win roughly correlate to what was shipped with the
 
 ## virtio-win driver signatures
 
-All the Windows binaries are from builds done on Red Hat’s internal build system, which are generated using publicly available code. The drivers are cryptographically signed with Red Hat’s vendor signature. However they are not signed with Microsoft’s [WHQL signature](https://docs.microsoft.com/en-us/windows-hardware/drivers/install/whql-release-signature). WHQL signed builds are only available with a paid RHEL subscription.
+All the Windows binaries are from builds done on Red Hat’s internal build system, which are generated using publicly available code. Windows 8+ drivers are cryptographically signed with Red Hat’s trest signature. [Test Signing](https://docs.microsoft.com/en-us/windows-hardware/drivers/install/test-signing) Windows 10+ drivers are signed with Microsoft attestation signature.[Microsof Attestation Signing](https://docs.microsoft.com/en-us/windows-hardware/drivers/dashboard/code-signing-attestation). However they are not signed with Microsoft’s [WHQL signature](https://docs.microsoft.com/en-us/windows-hardware/drivers/install/whql-release-signature). WHQL signed builds are only available with a paid RHEL subscription.
 
 The drivers are cryptographically signed with Red Hat’s vendor signature. However they are not signed with Microsoft’s WHQL signature.
 
-Warning: Due to the [signing requirements of the Windows Driver Signing Policy](https://docs.microsoft.com/en-us/windows-hardware/drivers/install/kernel-mode-code-signing-policy\--windows-vista-and-later-#signing-requirements-by-version), drivers which are not signed by Microsoft will not be loaded by some versions of Windows when [Secure Boot](https://docs.microsoft.com/en-us/windows-hardware/design/device-experiences/oem-secure-boot) is enabled in the virtual machine. See [bug #1844726](https://bugzilla.redhat.com/1844726).
+Warning: Due to the [signing requirements of the Windows Driver Signing Policy](https://docs.microsoft.com/en-us/windows-hardware/drivers/install/kernel-mode-code-signing-policy\--windows-vista-and-later-#signing-requirements-by-version), drivers which are not signed by Microsoft will not be loaded by some versions of Windows when [Secure Boot](https://docs.microsoft.com/en-us/windows-hardware/design/device-experiences/oem-secure-boot) is enabled in the virtual machine. See [bug #1844726](https://bugzilla.redhat.com/1844726). The test signed drivers requre enabling to load the test signed drivers.[Configuring the Test Computer to Support Test-Signing](https://docs.microsoft.com/en-us/windows-hardware/drivers/install/configuring-the-test-computer-to-support-test-signing) and installing Virtio_Win_Red_Hat_CA.cer test certificate located in "/usr/share/virtio-win/drivers/by-driver/cert/" folder.[Installing Test Certificates](https://docs.microsoft.com/en-us/windows-hardware/drivers/install/installing-test-certificates)
 
 
 ## `yum`/`dnf` repo