Install autoconf

Author: strk

.drone.yml

@@ -20,7 +20,7 @@ pipeline:
       - make lint
       - git --version
       - make test
-      - mkdir build &&
+      - apk add --update autoconf && mkdir build &&
         curl -sL "https://github.com/git/git/archive/v1.7.0.tar.gz" -o git.tar.gz &&
         tar -C build -xzf git.tar.gz &&
         cd build/git-1.7.0 &&