don't write header if no respective value present

Signed-off-by: Sebastian Schüpbach <sebastian.schuepbach@unibas.ch>
4 jobs for 0.1.8 in 3 minutes and 57 seconds (queued for 1 second)
latest
Status Job ID Name Coverage
  Test
passed test #62717
mbr

00:01:40

passed test-chart #62718
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00:00:13

 
  Publish
passed build-tagged-image #62719
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00:02:16

passed publish-chart #62720
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00:00:12