remove unneeded line

Author: mark-i-m

Diff for: ci/linkcheck.sh

@@ -5,7 +5,6 @@ if [ "$TRAVIS_EVENT_TYPE" = "cron" ] ; then # running in cron job
 
   echo "Doing full link check."
 elif [ "$CI" = "true" ] ; then # running in PR CI build
-  COMMIT_RANGE=$(echo $TRAVIS_COMMIT_RANGE | sed 's/\.\.\./../g')
   CHANGED_FILES=$(git diff --name-only $TRAVIS_COMMIT_RANGE | tr '\n' ' ')
   FLAGS="-f $CHANGED_FILES"