Add the Signature Verification to the Code to fix issue 828

[AmandineGagnon]

I attempted to fix the Issue #828 by adding the VM-Assert-Signature function to the code. This is my first pull request, so let me know if anything need to be changed or modified to be compliant with the process and coding guide.

[google-cla]

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[Ana06]

@AmandineGagnon thanks for the work you put in this PR. Packages using signature verification are not the easiest to start with 😅

I recommend you to at least check the following pages from our documentation:

• My first package walk through
• Coding Conventions
• Package Structure

Important things to notice:

• you need to accept the Google CLA for us to be able to merge the PR
• when modifying a package, you need to increase the version with the format specified in the documentation
• the package needs to create shortcut in the Tools directory using a category (as it was done before the update, but using the VM-Install-Shortcut helper directly as this was previously done inside the VM-Install-With-Installer helper function)
• The CI will run several checks (like the linter which you can also run locally and the Google CLI check) and all of them need to succeed to be able to merge the PR.

Let us know if you have questions.

[emtuls]

Closing as it has been fixed in #1091 now.