Strip ANSI color codes before parsing FAILED lines in cpu-multi-triage (#8882)
Fixes #8881.
The `Extract the failing test files` step in `cpu-multi-triage.yml`
greps the nightly log for `FAILED unit/...`, but the nightly pytest runs
with `--color=yes`, so every summary line carries ANSI sequences between
`FAILED` and the path:
```
\x1b[31mFAILED\x1b[0m unit/checkpoint/test_convert_checkpoint.py::TestCheckpointConvert::...
```
The pattern never matched, `failing-tests.txt` stayed empty, and the job
exited 1 ("no FAILED test files found in the nightly log") — see the
10-21 triage run:
https://github.com/deepspeedai/DeepSpeed/actions/runs/39548955267. As a
result no issue was auto-opened for the first `test`-class nightly
failure, and the `nightly-cpu-multi-last-green` tag stopped advancing.
Strip the escape codes in the pipeline before grepping, keeping the
colored log intact for humans reading the Actions UI:
```diff
gh run view "$NIGHTLY_RUN_ID" --log \
+ | sed 's/\x1b\[[0-9;]*m//g' \
| grep -oE 'FAILED unit/[^[:space:]]*\.py' | sort -u \
```
---------
Signed-off-by: Guokai Ma <guokai.ma@intel.com>
Signed-off-by: Ma, Guokai <guokai.ma@intel.com>