The wrong arch is being downloaded from f-droid

Expected behavior: Correctly determines the latest version number for the required architecture.
Result: The latest version for **x86_64** is always downloaded.

```bash
$ apkeep -a org.videolan.vlc -d f-droid -o arch=arm64-v8a .
Downloading org.videolan.vlc arch arm64-v8a...
org.videolan.vlc@arm64-v8a downloaded successfully!

$ aapt dump badging org.videolan.vlc@arm64-v8a.apk | grep native-code
native-code: 'x86_64'
```

some applications that have similar behavior:
- org.videolan.vlc
- io.element.android.x
- org.openobservatory.ooniprobe
- org.torproject.torbrowser (from https://guardianproject.info/fdroid/repo/?fingerprint=B7C2EEFD8DAC7806AF67DFCD92EB18126BC08312A7F2D6F3862E46013C7A6135)

Start by reproducing the F-Droid download with `apkeep -a org.videolan.vlc -d f-droid -o arch=arm64-v8a .`, then trace the F-Droid architecture-selection path in apkeep. Use `aapt dump badging ... | grep native-code` to verify the downloaded APK reports the requested architecture; done means arm64-v8a no longer resolves to x86_64 for the listed applications.

Written by the indexing model from the issue text.