Do not set an empty remark to avoid an empty signature notation

This is a workaround for GnuPG bug T5142.

GnuPG-bug-id: 5142
2 jobs for master in 10 minutes and 25 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Build
failed #78963
build_clazy_clang_tidy

00:04:18

passed #78962
linux kf5-qt5 qt5.14

00:06:06

0.0%
 
Name Stage Failure
failed
build_clazy_clang_tidy Build
-- Configuring incomplete, errors occurred!
See also "/builds/pim/kleopatra/build/CMakeFiles/CMakeOutput.log".
See also "/builds/pim/kleopatra/build/CMakeFiles/CMakeError.log".
Uploading artifacts for failed job
Uploading artifacts...
WARNING: JUnitTestResults.xml: no matching files
ERROR: No files to upload
Cleaning up file based variables
ERROR: Job failed: exit code 1