Bump riot version

src/freedombone-app-riot

 IN_DEFAULT_INSTALL=0
 SHOW_ON_ABOUT=1
 
-RIOT_VERSION='0.12.2'
+RIOT_VERSION='0.13.0'
 RIOT_FILENAME="riot-v${RIOT_VERSION}"
 RIOT_HASH='d0de730cb3e688040ba5c23680a676dabc94386830582842a4728767ed6dcd7f'
 RIOT_DOWNLOAD_URL="https://github.com/vector-im/riot-web/releases/download/v${RIOT_VERSION}"