Data race in E2E tests for headless

[NGTmeaty]

https://github.com/internetarchive/Zeno/actions/runs/17658909934/job/50188173120

==================
WARNING: DATA RACE
Write at 0x00c00004ccd0 by goroutine 108:
  github.com/internetarchive/Zeno/internal/pkg/archiver/headless.archivePage()
      /home/runner/work/Zeno/Zeno/internal/pkg/archiver/headless/archiver.go:339 +0x18a6
  github.com/internetarchive/Zeno/internal/pkg/archiver/headless.ArchiveItem()
      /home/runner/work/Zeno/Zeno/internal/pkg/archiver/headless/archiver.go:100 +0x674
  github.com/internetarchive/Zeno/internal/pkg/archiver.archive.gowrap1()
      /home/runner/work/Zeno/Zeno/internal/pkg/archiver/worker.go:230 +0x6b

Previous write at 0x00c00004ccd0 by goroutine 138:
  github.com/internetarchive/Zeno/internal/pkg/archiver/headless.archivePage.func2()
      /home/runner/work/Zeno/Zeno/internal/pkg/archiver/headless/archiver.go:235 +0x2814
  github.com/internetarchive/Zeno/internal/pkg/archiver/headless.archivePage.func2()
      /home/runner/work/Zeno/Zeno/internal/pkg/archiver/headless/archiver.go:159 +0x698
  github.com/go-rod/rod.(*HijackRouter).initEvents.func1.1()
      /home/runner/go/pkg/mod/github.com/go-rod/[email protected]/hijack.go:77 +0x1dd

Goroutine 108 (running) created at:
  github.com/internetarchive/Zeno/internal/pkg/archiver.archive()
      /home/runner/work/Zeno/Zeno/internal/pkg/archiver/worker.go:230 +0xabc
  github.com/internetarchive/Zeno/internal/pkg/archiver.(*archiver).worker()
      /home/runner/work/Zeno/Zeno/internal/pkg/archiver/worker.go:181 +0xe30
  github.com/internetarchive/Zeno/internal/pkg/archiver.Start.func1.gowrap1()
      /home/runner/work/Zeno/Zeno/internal/pkg/archiver/worker.go:85 +0x4f

Goroutine 138 (running) created at:
  github.com/go-rod/rod.(*HijackRouter).initEvents.func1()
      /home/runner/go/pkg/mod/github.com/go-rod/[email protected]/hijack.go:70 +0x11d
  runtime.call16()
      /opt/hostedtoolcache/go/1.25.1/x64/src/runtime/asm_amd64.s:774 +0x42
  reflect.Value.Call()
      /opt/hostedtoolcache/go/1.25.1/x64/src/reflect/value.go:365 +0xb5
  github.com/go-rod/rod.(*Browser).eachEvent.func1()
      /home/runner/go/pkg/mod/github.com/go-rod/[email protected]/browser.go:402 +0x5c8
  github.com/go-rod/rod.(*HijackRouter).Run()
      /home/runner/go/pkg/mod/github.com/go-rod/[email protected]/hijack.go:185 +0x42
  github.com/internetarchive/Zeno/internal/pkg/archiver/headless.archivePage.gowrap3()
      /home/runner/work/Zeno/Zeno/internal/pkg/archiver/headless/archiver.go:329 +0x17
==================