Update .travis.yml for proxy/ code removal

.travis.yml

@@ -4,32 +4,10 @@ dist: xenial
 
 go_import_path: git.torproject.org/pluggable-transports/snowflake.git
 
-addons:
-    apt:
-        sources:
-            - ubuntu-toolchain-r-test
-        packages:
-            - g++-5
-            - gcc-5
-
 go:
     - 1.13.x
 
-env:
-    - TRAVIS_NODE_VERSION="8" CC="gcc-5" CXX="g++-5"
-
-before_install:
-    - nvm install $TRAVIS_NODE_VERSION
-
-install:
-    - pushd proxy
-    - npm install
-    - popd
-
 script:
     - test -z "$(go fmt ./...)"
     - go vet ./...
     - go test -v -race ./...
-    - cd proxy
-    - npm run lint
-    - npm test