Remove the v2 upgrade feature flags

With force-upgrade-v2-encryption on, the clients loop on any v1 account that stays v1 on a vault route: the migration check runs fullSync(false), which writes lastSync, which triggers the scheduler again. No server response stops it, so don't serve the flag until the clients fix it.

pm-30144-sdk-key-rotation and pm-31050-no-logout-key-upgrade-rotation only serve that upgrade, so they go too.

src/config.rs

@@ -1508,11 +1508,8 @@ pub const SUPPORTED_FEATURE_FLAGS: &[&str] = &[
     // Key Management Team
     "biometrics-sdk-ipc",
     "windows-native-credential-sync",
-    "pm-30144-sdk-key-rotation",
-    "pm-31050-no-logout-key-upgrade-rotation",
     "enable-account-encryption-v2-jit-password-registration",
     "pm-27278-v2-password-registration",
-    "force-upgrade-v2-encryption",
     // Mobile Team
     "pm-34171-card-scanner",
     // Platform Team