Schedule integration tests on main branch erase coverage information

Hi Forum,
I have a question regarding Ci with coverage. On my main branch, I have a pipeline set up that outputs coverage information which I display in a badge on the project page. Works perfectly. Now, I set up a nightly scheduled pipeline for long-running integration tests, also on main. These integration tests don’t emit coverage information.
Today I noticed that after the scheduled pipeline ran, the coverage badge on the project page says coverage: unknown. When another commit is made on main, the normal pipeline runs and coverage is available again.
Is there a way to stop the scheduled pipeline from erasing coverage information?