Don't bootstrap twice on build providers

.travis.yml

@@ -16,7 +16,6 @@ install:
   - nvm install $NODE_VERSION
   - nvm use --delete-prefix $NODE_VERSION
   - npm install -g npm
-  - script/bootstrap
   - script/build --create-debian-package --create-rpm-package --compress-artifacts
 
 script: true

appveyor.yml

@@ -21,7 +21,6 @@ install:
 
 build_script:
   - cd %APPVEYOR_BUILD_FOLDER%
-  - script\bootstrap.cmd
   - script\build.cmd --code-sign --create-windows-installer --compress-artifacts
 
 test: off

circle.yml

@@ -24,7 +24,6 @@ dependencies:
     - npm install -g npm
 
   override:
-    - script/bootstrap
     - script/build --code-sign --compress-artifacts
 
   cache_directories: