Update grep line to hopefully build successfully

.travis.yml

@@ -11,7 +11,11 @@ cache:
 script: 
     - |
       docker run --rm \
-      --env-file <(env | grep -vE '\r|\n' | grep -iE 'DEBUG|NODE_|ELECTRON_|YARN_|NPM_|CI|CIRCLE|TRAVIS_TAG|TRAVIS|TRAVIS_REPO_|TRAVIS_BUILD_|TRAVIS_BRANCH|TRAVIS_PULL_REQUEST_|APPVEYOR_|CSC_|GH_|GITHUB_|BT_|AWS_|STRIP|BUILD_') \
+      $(env | \
+            grep -Eo '^[^\s=]*(DEBUG|NODE_|ELECTRON_|YARN_|NPM_|CI|CIRCLE|TRAVIS|APPVEYOR_|CSC_|_TOKEN|_KEY|AWS_|STRIP|BUILD_)[^\s=]*' | \
+            sed '/^$/d;s/^/-e /' | \
+            paste -sd ' ' \
+          ) \
       -v ${PWD}:/project \
       -v ~/.cache/electron:/root/.cache/electron \
       -v ~/.cache/electron-builder:/root/.cache/electron-builder \