fix wrong build number in output file name

Author: ki-bo

src/gitversion.sh

@@ -24,9 +24,9 @@ if [[ -n $JENKINS_SERVER_COOKIE ]]; then
   version=${GIT_COMMIT:0:7}
   buildnum=${BUILD_NUMBER}
 else
-  if [[ -n $TRAVIS_BRANCH ]]; then
-    branch=$TRAVIS_BRANCH
-    buildnum=$TRAVIS_BUILD_NUMBER
+  if [[ -n $GITHUB_RUN_NUMBER ]]; then
+    branch=$(git rev-parse --abbrev-ref HEAD)
+    buildnum=$GITHUB_RUN_NUMBER
   else
     branch=`git rev-parse --abbrev-ref HEAD`
     buildnum=man