remove unused appveyor, update to OpenBLAS v0.3.20

Author: mattip

.github/workflows/build.yml

@@ -13,7 +13,7 @@ on:
     branches: [ master ]
 
 env:
-  OPENBLAS_COMMIT: "5188aed"
+  OPENBLAS_COMMIT: "v0.3.20"
   OPENBLAS_ROOT: "c:\\opt"
 
 jobs:

.github/workflows/multibuild.yml

@@ -52,7 +52,7 @@ jobs:
             INTERFACE64: '1'
     env:
       REPO_DIR: OpenBLAS
-      OPENBLAS_COMMIT: "5188aed"
+      OPENBLAS_COMMIT: "v0.3.20"
       MACOSX_DEPLOYMENT_TARGET: 10.9
       MB_PYTHON_VERSION: ${{ matrix.python-version }}
       TRAVIS_PYTHON_VERSION: ${{ matrix.python-version }}

.travis.yml

@@ -2,7 +2,7 @@ env:
     global:
         # The archive that gets built has name from ``git describe`` on this
         # commit.
-        - OPENBLAS_COMMIT="5188aed"
+        - OPENBLAS_COMMIT="v0.3.20"
         - REPO_DIR=OpenBLAS
         # Following generated with:
         # travis encrypt -r MacPython/openblas-libs OPENBLAS_LIBS_STAGING_UPLOAD_TOKEN=<secret token value>

README.md

@@ -1,6 +1,7 @@
 # Building OpenBLAS
 
-This is a repository to trigger builds of OpenBLAS on Travis-CI and Appveyor.
+This is a repository to trigger builds of OpenBLAS on Travis-CI (for aarch64,
+ppc64, s390x) and github actions for all the others.
 
 The OpenBLAS libraries get uploaded to
 https://anaconda.org/multibuild-wheels-staging/openblas-libs/files