Support HTTP.jl 2

[asinghvi17]

Moves the HTTP.jl compat bound to 2 and migrates the call sites that 2.0 changed. julia compat moves to 1.10, the floor HTTP.jl 2.0 requires.

Verified locally on Julia 1.13: 372 passing with HTTP 2.6.7, identical to the HTTP 1.11 baseline on master.

Changes

Site	Change	Reason
Codecov.submit_generic, Codecov.upload_to_s3, Coveralls.post_request	String(msg) → string(msg)	2.0 drops Base.String(::Message). string yields the same status-line/headers/body dump these @debug statements already logged.
Codecov.upload_to_s3	dropped the header= keyword	2.0 raises MethodError on unrecognized request keywords (details below).
test/runtests.jl	JSON.parse(request.body) → JSON.parse(String(request.body))	Server-side request bodies are now HTTP.BytesBody rather than a byte vector.

Untouched by the migration: HTTP.post/HTTP.put verb calls, HTTP.Form and HTTP.Multipart uploads, the query and status_exception keywords, HTTP.serve!/HTTP.port/HTTP.header, and String(response.body). Each behaves the same under 2.0.

On the dropped header= keyword

HTTP.put has never recognized header — the keyword is headers — so 1.x silently discarded the dict, and the S3 upload has always gone out without Content-Type or x-amz-storage-class. HTTP.jl 2.0 rejects unknown keywords, which is what surfaced this.

This PR keeps the existing wire behavior instead of renaming the keyword to headers, because the target is an S3 presigned PUT: an x-amz-storage-class header outside the presigned X-Amz-SignedHeaders set makes S3 reject the upload with SignatureDoesNotMatch. Sending those headers is a separate change that also needs the signing side to cover them — happy to split it out if you'd like them enabled.

This path sits in submit_generic, which is already deprecated in favor of the Codecov uploader binary.

Notes for review

• julia = "1.10" is required rather than cosmetic: HTTP.jl 2.0 declares `julia = "1.10.0 - 1"
• This drops HTTP 0.8/0.9/1 support
• HTTP.jl 1.x → 2.0 migration guide

🤖 Generated with Claude Code

[DilumAluthge]

CI is sad?

[asinghvi17]

The CI issues are all coming from Reseau.jl it seems, cc @quinnj