Defective support of testnet-only addreses (kQ...) in testnet mode

[justdmitry]

In testnet mode, website still operates addresses "in mainnet form" EQ... instead of "kQ... (without honouring "testnet-only" flag).

"Wrong" address is written into Jetton metadata and website does not allow to edit Jetton (later) - Edit button does not shown.

Tested with OpenMask Beta version 0.18.21 (last published) chrome plugin.