ci: increase Windows release workflow timeouts

[bolinfest]

Why

#20271 increased the 90-minute timeout in rust-release.yml, but it did not update the reusable Windows workflow in rust-release-windows.yml. As a result, the Windows release compile jobs were still capped at 60 minutes and the windows-x64 primary build could continue timing out.

We are keeping the existing 90-minute timeout in rust-release.yml. That increase was still directionally correct because the top-level release build benefits from extra headroom; the mistake was assuming it also covered the reusable Windows jobs.

What Changed

• increase the reusable Windows release workflow timeouts in rust-release-windows.yml from 60 minutes to 90 minutes
• update the comment in rust-release.yml so it no longer implies that the top-level timeout covers the Windows reusable jobs