simplify script that pushes to coverity

tools/travis/travis_push_coverity.sh

@@ -4,22 +4,9 @@ set -ev
 # This script is run by travis-ci and pushes the first commit
 # of the day to the coverity scan service
 
-git fetch origin coverity_scan
 COMMITS=`git log --oneline --since=today.midnight | wc -l`
 if [ "$COMMITS" -le 1 ]; then
-    #first commit a day - push changes to branch coverity_scan
-    git clone -b coverity_scan https://$GITAUTH@github.com/acplt/open62541
-    cd open62541
-    git fetch origin
-    git merge origin/master
-    git config --global user.email "open62541-travis-ci@users.noreply.github.com"
-    git config --global user.name "Open62541 travis-ci"
-    git config --global push.default simple
-    git add *
-    git commit -am "push to coverity scan by travis-ci"
-    git push https://$GITAUTH@github.com/acplt/open62541
-    cd ..
-    rm -rf open62541
+    git push --force https://$GITAUTH@github.com/open62541/open62541 coverity_scan
 else
     echo "Not the first commit of the day - no push to coverity required"
 fi