GH/releases/continuous: add link for alt builds outside GH

Author: MartinPulec

.github/scripts/create_release.sh

@@ -30,7 +30,11 @@ fi
 DATE=$(date -Iminutes)
 if [ "$VERSION" = continuous ]; then
         TITLE='continuous builds'
-        SUMMARY='Current builds from Git master branch. macOS alternative build is rebuilt daily, Linux ARM builds weekly. Archived builds can be found [here](https://frakira.fi.muni.cz/~xpulec/ug-nightly-archive/).'
+        SUMMARY="Current builds from Git master branch. macOS alternative\
+ build is rebuilt daily, Linux ARM builds weekly. Archived builds can be\
+ found [here](https://frakira.fi.muni.cz/~xpulec/ug-nightly-archive/),\
+ additional alternative builds\
+ [here](https://frakira.fi.muni.cz/~xpulec/ug-alt-builds/)."
         PRERELEASE=true
 else
         TITLE="UltraGrid $VERSION"