CI_COMMIT_MESSAGE regex examples in `rules` should not use prefix matching due to trailing new line
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Documentation can be improved by using more general examples, which do not fail to work. See pages regarding `workflow:rules`:
- https://docs.gitlab.com/ee/ci/yaml/index.html#workflowrules
- https://docs.gitlab.com/ee/ci/yaml/workflow.html#workflow-rules-examples
Here the default example for using `CI_COMMIT_MESSAGE` to much a suffix _-draft_ is:
```yaml
if: $CI_COMMIT_MESSAGE =~ /-draft$/
```
Due to the way how `git commit -m my-draft` works, it will add a trailing new line to the commit message, which is not obvious. Therefore, for a beginner to `rules` the above example will always fail to work. It would be more save to provide an example with a prefix notation, which will not fail to work in any environment:
```yaml
if: $CI_COMMIT_MESSAGE =~ /^draft/
```
issue