Try setting the variable

ci/build_zip.sh

@@ -1,11 +1,11 @@
 #!/bin/bash
 
 cd ../
-mkdir release-temp
+mkdir $VERSION_NUMBER
-TARGETDIR='release-temp';for file in *;do test "$file" != "$TARGETDIR" && cp -r "$file" "$TARGETDIR/";done
+TARGETDIR=$VERSION_NUMBER;for file in *;do test "$file" != "$TARGETDIR" && cp -r "$file" "$TARGETDIR/";done
 
 # Remove files that we don't want to bundle
-cd release-temp
+cd $VERSION_NUMBER
 rm -rf ci
 #rm .gitignore
 #rm .gitlab-ci.yml
@@ -14,5 +14,5 @@ rm apidoc.json
 rm CONTRIBUTING.md
 
 cd ../
-zip -r release.zip release-temp
+zip -r release.zip $VERSION_NUMBER
-rm -rf release-temp
+rm -rf $VERSION_NUMBER