Simplify git setup by exiting on .git presence

entrypoints/setup_git.sh

@@ -2,25 +2,21 @@
 
 [ -e ".finished" ] && return 0
 
-apk update && apk add git
-
-git remote || INIT=true
+ls .git && return 0
 
 echo "${GITHUB_REPO}" | grep -q "#" && TAG="${GITHUB_REPO#*#}" || TAG=
 
-if [ "${INIT}" ]
+apk update && apk add git
+git init
+chown -R "$(find . -maxdepth 1 -exec ls -ld {} + | awk '{print $3":"$4}' | tail -n1)" .git
+git config --global --add safe.directory "${PWD}"
+REPO="${GITHUB_REPO%%#*}"
+git remote add origin "${REPO}"
+git fetch
+DEFAULT_BRANCH=$(git remote show origin | sed -n '/HEAD branch/s/.*: //p')
+git reset --hard origin/"${DEFAULT_BRANCH}"
+git clean -fd
+if [ -n "${TAG}" ]
 then
-    git init
-    chown -R "$(find . -maxdepth 1 -exec ls -ld {} + | awk '{print $3":"$4}' | tail -n1)" .git
-    git config --global --add safe.directory "${PWD}"
-    REPO="${GITHUB_REPO%%#*}"
-    git remote add origin "${REPO}"
-    git fetch
-    DEFAULT_BRANCH=$(git remote show origin | sed -n '/HEAD branch/s/.*: //p')
-    git reset --hard origin/"${DEFAULT_BRANCH}"
-    git clean -fd
-    if [ -n "${TAG}" ]
-    then
-        git checkout "${TAG}"
-    fi
+    git checkout "${TAG}"
 fi