Revert "Update Travis CI and CircleCI to use macOS 10.14 " and "Change examples to use macOS >= 10.14"

This reverts commits 870bf3f and cd53552.

Author: YannickJadoul

.circleci/config.yml

@@ -3,7 +3,7 @@ version: 2
 jobs:
   osx-python3.6:
     macos:
-      xcode: 10.2.1
+      xcode: 9.4.1
     environment:
       PYTHON: python3
     steps:

.travis.yml

@@ -28,7 +28,6 @@ jobs:
 
     - name: macOS | x86_64 | Python 3.x
       os: osx
-      osx_image: xcode10.2
       env:
         - PYTHON=python3
         - PYTEST_ADDOPTS='-k "unit_test or test_0_basic" --suppress-no-test-exit-code'

README.md

@@ -67,8 +67,6 @@ jobs:
     - services: docker
     # and a mac build
     - os: osx
-      # PyPy 7.3.2 needs macOS >= 10.14
-      osx_image: xcode10.2
       language: shell
     # and a windows build
     - os: windows

examples/circleci-minimal.yml

@@ -19,8 +19,7 @@ jobs:
   osx-wheels:
     working_directory: ~/osx-wheels
     macos:
-      # PyPy 7.3.2 needs macOS >= 10.14
-      xcode: 10.2.1
+      xcode: 10.0.0
     steps:
       - checkout
       - run:

examples/travis-ci-deploy.yml

@@ -9,8 +9,6 @@ jobs:
     - services: docker
     # and a mac build
     - os: osx
-      # PyPy 7.3.2 needs macOS >= 10.14
-      osx_image: xcode10.2
       language: shell
     # and a windows build
     - os: windows

examples/travis-ci-minimal.yml

@@ -15,8 +15,6 @@ jobs:
       arch: s390x
     # and a mac build
     - os: osx
-      # PyPy 7.3.2 needs macOS >= 10.14
-      osx_image: xcode10.2
       language: shell
     # and a windows build
     - os: windows

examples/travis-ci-test-and-deploy.yml

@@ -64,8 +64,6 @@ jobs:
     - stage: deploy
       name: Build and deploy macOS wheels
       os: osx
-      # PyPy 7.3.2 needs macOS >= 10.14
-      osx_image: xcode10.2
       language: shell
       install: python3 -m pip install cibuildwheel==1.6.4
       script: python3 -m cibuildwheel --output-dir wheelhouse