fix(build): Allow update-apps.sh script to work with non-master branches

Signed-off-by: provokateurin <kate@provokateurin.de>

build/update-apps.sh

@@ -10,9 +10,23 @@
 # It automatically:
 # - goes through all apps which are not shipped via server
 # - shows the app name in bold and uses whitespace for separation
-# - changes to master and pulls quietly
+# - changes to master/main and pulls quietly
 # - shows the 3 most recent commits for context
-# - removes branches merged into master
+# - removes branches merged into master/main
 # - … could even do the build steps if they are consistent for the apps (like `make`)
 
-find apps* -maxdepth 2 -name .git -exec sh -c 'cd {}/../ && printf "\n\033[1m${PWD##*/}\033[0m\n" && git checkout master && git pull --quiet -p && git --no-pager log -3 --pretty=format:"%h %Cblue%ar%x09%an %Creset%s" && printf "\n" && git branch --merged master | grep -v "master$" | xargs git branch -d && cd ..' \;
+set -euo pipefail
+
+for path in apps*/*/.git; do
+	(
+		path="$(dirname "$path")"
+		cd "$path"
+		printf "\n\033[1m${PWD##*/}\033[0m\n"
+		branch="$(git remote show origin | sed -n '/HEAD branch/s/.*: //p')"
+		git checkout "$branch"
+		git pull --quiet -p
+		git --no-pager log -3 --pretty=format:"%h %Cblue%ar%x09%an %Creset%s"
+		printf "\n"
+		git branch --merged "$branch" | grep -v "$branch$" | xargs git branch -d || true
+	)
+done