Protect-GuestConfigurationPackage doesn't timestamp packages

#### Details of the scenario you tried and the problem that is occurring

I recently set up signing of GC packages via Protect-GuestConfigurationPackage. The result is a package that is signed, but not timestamped, which will cause problems if the cert expires and we haven't redeployed using the updated cert.

#### Verbose logs showing the problem

```
PS C:\Users\ewadmn11\Downloads λ Get-AuthenticodeSignature .\EwaCisScore.cat

Directory: C:\Users\ewadmn11\Downloads

SignerCertificate Status StatusMessage Path
----------------- ------ ------------- ----
thumb Valid Signature verified. EwaCisScore.cat

PS C:\Users\ewadmn11\Downloads λ Get-AuthenticodeSignature .\EwaCisScore.cat | fl

SignerCertificate : [Subject]
CN=Enterprise Windows and Azure Administration, O=Indiana University, L=Bloomington, S=Indiana, C=US

[Issuer]
CN=Indiana University BL Issuing CA 2, OU=UITS, O=IU

[Serial Number]
4400097EC5BDC2D69681F636EA000100097EC5

[Not Before]
3/5/2026 12:55:22 PM

[Not After]
3/4/2028 12:55:22 PM

[Thumbprint]
thumb

TimeStamperCertificate :
Status : Valid
StatusMessage : Signature verified.
Path : C:\Users\ewadmn11\Downloads\EwaCisScore.cat
SignatureType : Authenticode
IsOSBinary : False
```

#### Suggested solution to the issue

Add a parameter and tooling to support timestamping.

#### The operating system the target node is running

Windows Server 2025

#### Version and build of PowerShell the target node is running

7.5.4

#### Version of the module that was used

4.11.0