Fix travis linux build

.travis.yml

@@ -17,7 +17,7 @@ before_install:
   - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then sudo apt-get update -qq; fi
   - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then sudo apt-get install -qq lv2-dev python3-pip ninja-build autoconf m4 libtool; fi
   - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then sudo -H pip3 install --upgrade pip; fi
-  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then sudo pip3 install meson; fi
+  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then sudo -H pip3 install meson; fi
 
 script:
   - chmod +x install.sh && ./install.sh