Access the current tenant in the importer resolveRecord() method

public function resolveRecord(): ?User
    {
        $team = Filament::getTenant();

        $user = User::firstOrNew([
            'email' => $this->data['email'],
        ]);

        $team->members()->associate($user->id);

        return $user;
    }

public function members(): BelongsToMany
    {
        return $this->belongsToMany(User::class);
    }