cabal update weirdness behind multilevel proxy

In a McDonalds, cabal update failed the first time with "cabal: Codec.Compression.Zlib: premature end of compressed stream", but the second time it said "Local and remote files match" despite only having downloaded a prefix of the 00-index.tar.gz and not being able to install any packages.

https://tmp.kitenet.net/cabal/ has the files download and a cabal -v3 log and curl -v log.

```
joeyh: so you've got two additional proxies compared to me
a varnish one and a localhost squid one
the first proxy is our CDN, and you've got two others you're behind
for a total of 3
neither of those proxies are on my machine, it's the network here I suppose
I got a good update using a VPN
hmm, and they only speak HTTP 1.0
so my response here is HTTP 1.1
but yours is HTTP 1.0
```

Also got the codec error on download of some packages from hackage. This left the cached and corrupt package tarballs in .cabal and prevented cabal install from installing them even after I got to a good network.

cabal-install version 1.22.6.0
using version 1.22.5.0 of the Cabal library