force build because node platform doesn't respect buildfile

.ebextenstions/containercommands.config

@@ -0,0 +1,4 @@
+container_commands:
+  00_build_sh:
+    command: ./build.sh
+    ignoreErrors: false

build.sh

@@ -1,10 +1,16 @@
 #!/usr/bin/env bash
 
+echo installing yarn
+
 # install yarn
 sudo npm install yarn -g
 
+echo link
+
 # make sure it's in path
 sudo ln -s "$(npm bin --global)"/yarn /usr/bin/yarn
 
+echo try to build
+
 # build it
 sudo yarn build