It is common for people to make kiddush over whisky or other spirits on Shabbat morning whether at home or in shul. Ideally, we should make kiddush on wine. On Friday night you cannot use drinks other than wine or grape juice; if you don’t have either, you should make kiddush on bread.
On Shabbat morning, there is more flexibility. Rav Moshe Feinstein rules that you may make day-time kiddush on any alcoholic drink you would serve a guest. This leniency is because daytime kiddush is only of rabbinic origin, while night-time kiddush is of biblical origin.
However, you are supposed to drink at least the majority of a revi’it, a measure of liquid volume. The majority of a revi’it comes out to be around 1.7 fluid ounces. (Some authorities opined that one need not drink that much liquor for kiddush.) A normal shot glass holds around one fluid ounce. If you want to avoid halachic complication, better to make kiddush on wine.