Drone signs its comments

Signed-off-by: tobiasKaminsky <tobias@kaminsky.me>

scripts/analysis/lint-up.rb

@@ -186,7 +186,7 @@ system ("git remote add origin https://" + git_user + ":" + git_token + "@github
 system ('git add ' + PREVIOUS_LINT_RESULTS_FILE)
 
 # commit changes; Add "skip ci" so that we don't accidentally trigger another Drone build
-system ('git commit -m "Drone: update Lint results to reflect reduced error/warning count [skip ci]" ')
+system ('git commit -sm "Drone: update Lint results to reflect reduced error/warning count [skip ci]" ')
 
 # push to origin
 system ('git push origin HEAD:' + git_branch)