MAINT: Simplify CIBUILDWHEEL command to avoid pip install error (#34)

* MAINT: Remove manual pip upgrade

* FIX: Try again

* FIX: Typo

Author: larsoner

azure-pipelines.yml

@@ -11,8 +11,7 @@ variables:
   CIBW_SKIP: "cp27-* cp34-* pp27-*"
   CIBW_TEST_COMMAND: "python -c \"import rtmixer; print(rtmixer.__version__)\""
   CIBW_BUILD_VERBOSITY: "2"
-  CIBW_BEFORE_BUILD: "pip install -U pip setuptools"
-  CIBW_BEFORE_BUILD_LINUX: "yum install -y portaudio"
+  CIBW_BEFORE_BUILD_LINUX: "yum install -y portaudio; pip install -U pip setuptools"
 jobs:
 - job: linux
   pool: {vmImage: 'Ubuntu-16.04'}