[Rust] IPC reader must respect continuation markers

[asfimport]

A continuation marker (value of 0xffffffff) in a message size block is
used to align the next block to an 8-byte boundary. This value needs to
be skipped over if encountered.

Reporter: Max Burke / @maxburke
Assignee: Max Burke / @maxburke

Related issues:

• [Rust] Linting GitHub Actions task failing (duplicates)

PRs and other links:

• GitHub Pull Request #6724
• GitHub Pull Request #6791

_{Note: This issue was originally created as ARROW-8225. Please see the migration documentation for further details.}

[asfimport]

Kouhei Sutou / @kou:
Issue resolved by pull request 6724
#6724