appimage: update package in dockerfile
appimage: update package in dockerfile

Ubuntu no longer serves old version

vialectrum/vialectrum,spesmilo/electrum,wakiyamap/electrum-mona,spesmilo/electrum,pooler/electrum-ltc,vialectrum/vialectrum,wakiyamap/electrum-mona,vialectrum/vialectrum,wakiyamap/electrum-mona,pooler/electrum-ltc,pooler/electrum-ltc,wakiyamap/electrum-mona,spesmilo/electrum,spesmilo/electrum,pooler/electrum-ltc