Add deb target to linux build (#1093)

Summary:
I'm adding the `.deb` option to linux build, it makes easier to install.
```bash
cd desktop
yarn build --linux --linux-deb
```

## Changelog

- Add deb target to linux build
Pull Request resolved: https://github.com/facebook/flipper/pull/1093

Reviewed By: mweststrate

Differential Revision: D21378807

Pulled By: passy

fbshipit-source-id: a72a85705d3c464cddd80091d38c92012bdbee2c

desktop/scripts/build-release.ts

@@ -80,6 +80,13 @@ async function buildDist(buildFolder: string) {
   }
   if (process.argv.indexOf('--linux') > -1) {
     targetsRaw.push(Platform.LINUX.createTarget(['zip']));
+
+    const argv = process.argv.slice(2);
+    if (argv.indexOf('--linux-deb') > -1) {
+      // linux targets can be:
+      // AppImage, snap, deb, rpm, freebsd, pacman, p5p, apk, 7z, zip, tar.xz, tar.lz, tar.gz, tar.bz2, dir
+      targetsRaw.push(Platform.LINUX.createTarget(['deb']));
+    }
   }
   if (process.argv.indexOf('--win') > -1) {
     targetsRaw.push(Platform.WINDOWS.createTarget(['zip']));