Fix activated_path_skip on repeated running of emsdk_env.sh (#1250)

The first time around `node` was being correctly added to the PATH, but
the second time around this code was observing the emsdk copy of node
in the PATH and assuming it could be skipped.

Fixes: #1240

.circleci/config.yml

@@ -80,6 +80,7 @@ jobs:
       - run:
           name: Install debian packages
           command: apt-get update -q && apt-get install -q -y cmake build-essential openjdk-8-jre-headless ksh zsh
+      - run: test/test_node_path.sh
       - run: test/test.sh
       - run: test/test_source_env.sh
       - run: