fix: reload file need use privious pos

[luohoufu]

What does this PR do

This pull request includes a small but important change to the modules/queue/disk_queue/consumer.go file. The change ensures that the read position is reset to the previous position when an invalid message size is detected, which helps to handle partial file loads more gracefully.

• modules/queue/disk_queue/consumer.go: Added a line to reset d.readPos to previousPos when an invalid message size is detected, improving the handling of partial file loads.

Rationale for this change

Standards checklist

• The PR title is descriptive
• The commit messages are semantic
• Necessary tests are added
• Updated the release notes
• Necessary documents have been added if this is a new feature
• Performance tests checked, no obvious performance degradation

[medcl]

Awesome, good catch.