tests: add tests for DNS-over-HTTPS to iroh-dns-server

[Frando]

Description

Our DoH support in iroh-dns-server is broken: #3737

We didn't have any tests for DoH before.

This adds end-to-end tests that test resolving DoH records via HTTP and HTTPS via reqwest, and via hickory-resolver.

While working on this, I realized that we currently do not change the storage path in tests, which is bad can can lead to very unexpected behavior when running tests concurrently. This also fixes that by allowing to pass in the storage path.

Breaking Changes

Notes & open questions

Change checklist

• Self-review.
• Documentation updates following the style guide, if relevant.
• Tests if relevant.
• All breaking changes documented.
  • List all breaking changes in the above "Breaking Changes" section.
  • Open an issue or PR on any number0 repos that are affected by this breaking change. Give guidance on how the updates should be handled or do the actual updates themselves. The major ones are:
    • quic-rpc
    • iroh-gossip
    • iroh-blobs
    • dumbpipe
    • sendme

[github-actions]

Documentation for this PR has been generated and is available at: https://n0-computer.github.io/iroh/pr/3745/docs/iroh/

Last updated: 2025-12-08T15:14:00Z

[github-actions]

Netsim report & logs for this PR have been generated and is available at: LOGS
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Last updated for commit: a6f33b8

[dignifiedquire]

---- http::tests::test_doh stdout ----

thread 'http::tests::test_doh' (6480) panicked at /cargo/registry/src/index.crates.io-1949cf8c6b5b557f/tracing-subscriber-0.3.22/src/fmt/mod.rs:1247:16:
Unable to install global subscriber: SetGlobalDefaultError("a global default trace dispatcher has already been set")
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

the cross failure seems real