Unable to count as a failures: <system-err> tags

### Jenkins and plugins versions report

```text
Jenkins cannot report failures. So they are not visible when jenkins finishes and xml report contains system-err tag.
Example:

...

...

```

### What Operating System are you using (both controller, and any agents involved in the problem)?

Windows 11

### Reproduction steps

Just look reports containing system-err tags and not containing failures.

Report will show all testcases passed which is wrong because should be considered.

### Expected Results

Jenkins should be able to recognize system-err tags

### Actual Results

system-err tags are not visible on Jenkins

### Anything else?

N/A

Start by reproducing the report behavior with the supplied JUnit XML example containing a tag and no failure element. Inspect the report parsing path for how system-err is handled, then verify that the displayed testcase result matches the intended treatment of this tag.

Written by the indexing model from the issue text.