build: incl "frozenlist" dep as pure-python, without C stuff
build: incl "frozenlist" dep as pure-python, without C stuff

While attempting to reproducibly build the qml android apk, one of the differences
was due to the "frozenlist" dependency (pulled in by aiohttp) - the compiled C parts
were not deterministic. By setting this env var, we can opt-out [0] of all the C
accelerated parts and just use the pure-python implementation. We are already doing
the same for other aiohttp-related packages anyway.

[0]: https://github.com/aio-libs/frozenlist/blob/c2794cac120ea9c89ec59205f561b57e6ad1dae7/setup.py#L7

pooler/electrum-ltc,pooler/electrum-ltc,pooler/electrum-ltc,pooler/electrum-ltc,spesmilo/electrum,spesmilo/electrum,spesmilo/electrum,spesmilo/electrum