Track issue of fixing `BR download SST consider disk usage and report error if almost full` in tiflash

[JaySon-Huang]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

See tikv/tikv#17224 for details. That commit can prevent running of out disk space when BR restore.

Backport to tiflash (tiflash-proxy) in the LTS branches:

• master: update proxy of master to raftstore-proxy #9236
• release-8.1: update proxy of release-8.1 to raftstore-proxy-8.1 #9409
• release-7.5: proxy: Upgrade TiFlash Proxy to fix known issue about BR and import #9706
• release-7.1: TBD

2. What did you expect to see? (Required)

3. What did you see instead (Required)

4. What is your TiFlash version? (Required)

[JaySon-Huang]

close as this has been fixed on the master branch. The cherry-pick to LTS branch will be done in later PRs