What it mean Precommit failed?

Hello,
What does it mean:

Checking code/codeabbey/135/adrianfcn.c ...

[splint] splint................................................................Passed
hookid: splint

Splint 3.1.2 --- 01 Dec 2016

Finished checking --- no warnings

[rubocop] rubocop..........................................(no files to check)Skipped
[slim-lint] slim-lint......................................(no files to check)Skipped
See (future:webpage docs|now:https://pre-commit.com/)
Precommit failed
mimetypes and charsets check OK, continue checks...
ERROR: Job failed: exit code 1

Can you paste the entire log or the link to the failed job please? this output does not provide enough information

Yes, this is the link for the failed job:
https://gitlab.com/autonomicmind/training/-/jobs/273513991

This is the actual error:
[trailing-whitespace] Trim Trailing Whitespace.................................Failed

This issue has been already addressed on this community:

Make sure to check the CI logs and search in the already existing posts before creating duplicated threads.

You should also make a research on that issue to understand what means and how to fix it.