fix: customize postinst by architecture (microsoft#259280)

Fixes microsoft#258886

Author: rzhao271

build/gulpfile.vscode.linux.js

@@ -107,6 +107,7 @@ function prepareDebPackage(arch) {
 
 		const postinst = gulp.src('resources/linux/debian/postinst.template', { base: '.' })
 			.pipe(replace('@@NAME@@', product.applicationName))
+			.pipe(replace('@@ARCHITECTURE@@', debArch))
 			.pipe(rename('DEBIAN/postinst'));
 
 		const templates = gulp.src('resources/linux/debian/templates.template', { base: '.' })

resources/linux/debian/postinst.template

@@ -96,7 +96,7 @@ Types: deb
 URIs: https://packages.microsoft.com/repos/code
 Suites: stable
 Components: main
-Architectures: amd64,arm64,armhf
+Architectures: @@ARCHITECTURE@@
 Signed-By: $CODE_TRUSTED_PART
 EOF
 			if [ -f "$CODE_SOURCE_PART" ]; then
@@ -105,7 +105,7 @@ EOF
 		else
 			echo "### THIS FILE IS AUTOMATICALLY CONFIGURED ###
 # You may comment out this entry, but any other modifications may be lost.
-deb [arch=amd64,arm64,armhf] https://packages.microsoft.com/repos/code stable main" > $CODE_SOURCE_PART
+deb [arch=@@ARCHITECTURE@@] https://packages.microsoft.com/repos/code stable main" > $CODE_SOURCE_PART
 		fi
 
 		# Sourced from https://packages.microsoft.com/keys/microsoft.asc