WireGuardApp: Add back the wireguard-go version extraction script and use WIREGUARD_GO_VERSION directly

Avoids linking against libwg-go.a in order to access the WireGuard backend version.

Signed-off-by: Andrej Mihajlov <and@mullvad.net>

Sources/WireGuardApp/UI/iOS/ViewController/SettingsTableViewController.swift

@@ -152,7 +152,7 @@ extension SettingsTableViewController {
                 }
                 cell.value = appVersion
             } else if field == .goBackendVersion {
-                cell.value = wireGuardVersion
+                cell.value = WIREGUARD_GO_VERSION
             }
             return cell
         } else if field == .exportZipArchive {

Sources/WireGuardApp/UI/macOS/AppDelegate.swift

@@ -208,7 +208,7 @@ extension AppDelegate {
         }
         let appVersionString = [
             tr(format: "macAppVersion (%@)", appVersion),
-            tr(format: "macGoBackendVersion (%@)", wireGuardVersion)
+            tr(format: "macGoBackendVersion (%@)", WIREGUARD_GO_VERSION)
         ].joined(separator: "\n")
         let donateString = NSMutableAttributedString(string: tr("donateLink"))
         donateString.addAttribute(.link, value: "https://www.wireguard.com/donations/", range: NSRange(location: 0, length: donateString.length))