Use HTTPS for the apt repository

[fmarier]

Fix for #203832

How to test:

1. Build the .deb package.
2. dpkg -i the freshly-built package.
3. Look in /etc/apt/sources.list.d/vscode.list for an https:// URL.

[fmarier]

It could also be worthwhile to upgrade existing installations similar to

vscode/resources/linux/debian/postinst.template

Lines 43 to 45 in c9f0aa5

	elif grep -Eq "http:\/\/packages\.microsoft\.com\/repos\/vscode" $CODE_SOURCE_PART; then
	# Migrate from old repository
	WRITE_SOURCE=1

, but this requires building and testing and I don't have time for that right now. I suggest we leave that for a future follow-up.

This PR will at least address new installations.

[Tyriar]

This was proposed before in #57992 (comment), you can see the reasoning for it being plain http there

[fmarier]

@Tyriar That reasoning made sense 6 years ago, but if you look at https://packages.debian.org/unstable/apt-transport-https, apt-transport-https is no longer a separate package since the functionality was moved to apt directly in version 1.5.

The oldest supported version of Ubuntu (18.04) uses apt 1.6 and the oldest supported version of Debian (10) uses apt 1.8. Therefore, this will be a seamless upgrade for new installs.

I don't have the permissions to reopen this PR, so please consider this a request for re-review.

[Tyriar]

Nice, thanks for the follow up!

@rzhao271 FYI, could you take a quick look and approve this, want to make sure you're aware in case anything goes wrong.