bad signature error slow internet connection.

I am using iSH on my iPhone and my iPhone has a 64k mobile internet connection. I get a "bad signature" error when larger packages are downloaded. Smaller packages download without error.

```
iPhone:~# apk add gcc
fetch http://apk.ish.app/v3.14-2023-05-19/community/x86/APKINDEX.tar.gz
ERROR: http://apk.ish.app/v3.14-2023-05-19/community: BAD signature
(1/2) Installing binutils (2.35.2-r2)
ERROR: Failed to create usr/lib/libbfd-2.35.2.so: Connection aborted
ERROR: binutils-2.35.2-r2: BAD signature
(2/2) Installing gcc (10.3.1_git20210424-r2)
ERROR: Failed to create usr/bin/gcc: Connection aborted
ERROR: gcc-10.3.1_git20210424-r2: BAD signature
2 errors; 90 MiB in 59 packages
iPhone:~#
```

Reproduce the report in iSH on an iPhone using a slow 64k connection and the `apk add gcc` command shown. Inspect the package-download path for the `BAD signature` and `Connection aborted` errors; done means determining whether the failure is caused by slow downloads and identifying a confirmed fix or limitation.

Written by the indexing model from the issue text.