CI: Use pip because setuptools will not avoid an incompatible numpy

Author: effigies

.github/workflows/stable.yml

@@ -21,7 +21,7 @@ jobs:
         os: ['ubuntu-latest', 'windows-latest', 'macos-latest']
         python-version: [3.6, 3.7, 3.8, 3.9]
         architecture: ['x64', 'x86']
-        install: ['setup']
+        install: ['pip']
         check: ['test']
         pip-flags: ['']
         depends: ['REQUIREMENTS']
@@ -54,7 +54,7 @@ jobs:
           # Clean install imports only with package-declared dependencies
           - os: ubuntu-latest
             python-version: 3.6
-            install: setup
+            install: pip
             check: skiptests
             pip-flags: ''
             depends: ''

tools/ci/build_archive.sh

@@ -21,6 +21,8 @@ elif [ "$INSTALL_TYPE" == "wheel" ]; then
 elif [ "$INSTALL_TYPE" == "archive" ]; then
     export ARCHIVE="package.tar.gz"
     git archive -o $ARCHIVE HEAD
+elif [ "$INSTALL_TYPE" == "pip" ]; then
+    export ARCHIVE="."
 fi
 
 set +eux