Reduce usages of Vector::Append(const U*, wtf_size_t)

* Update ReplayingBytesConsumer::Command constructors
  - Change pointer+size arguments to a base::span
  - Change nul-terminated pointer argument to an array

This CL has no behavior changes.

Bug: 351564777
Change-Id: I91aacb668809ce8a1c54614180cdde66865e6d92
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6058989
Reviewed-by: Fredrik Söderquist <fs@opera.com>
Commit-Queue: Fredrik Söderquist <fs@opera.com>
Auto-Submit: Kent Tamura <tkent@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1389688}