Minor grammatical fix to runner deletion message (#7479)
WIP until someone else tells me whether the whole message should be changed or whether `s/mark/marked/` is enough.
I am honestly not sure what "It may break building workflow." means in this context either but it doesn't sound correct to me.
## Checklist
*snipped* - this is really minor, please let me know if there's a better checklist to use for changes like this
### Release notes
- [x] I do not want this change to show in the release notes. [Change is too minor]
Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/7479
Reviewed-by: Earl Warren <earl-warren@noreply.codeberg.org>
Co-authored-by: voltagex <git@voltagex.org>
Co-committed-by: voltagex <git@voltagex.org>
authored by