ci: Add schedule and workflow_dispatch support

.github/workflows/test.yml

@@ -1,36 +1,43 b''
 name: Run tests
 
-on: [push, pull_request]
+on:
+  push:
+  pull_request:
+  # Run weekly on Monday at 1:23 UTC
+  schedule:
+  - cron:  '23 1 * * 1'
+  workflow_dispatch:
+
 
 jobs:
   test:
     runs-on: ubuntu-latest
     strategy:
       matrix:
         python-version: [3.7, 3.8, 3.9]
 
     steps:
     - uses: actions/checkout@v2
     - name: Set up Python ${{ matrix.python-version }}
       uses: actions/setup-python@v2
       with:
         python-version: ${{ matrix.python-version }}
     - name: Install and update Python dependencies
       run: |
         python -m pip install --upgrade pip setuptools wheel
         python -m pip install --upgrade -e file://$PWD#egg=ipython[test]
         python -m pip install --upgrade --upgrade-strategy eager trio curio 
         python -m pip install --upgrade pytest pytest-trio 'matplotlib!=3.2.0'
         python -m pip install --upgrade check-manifest pytest-cov anyio
     - name: Check manifest
       run: check-manifest
     - name: iptest
       run: |
         cd /tmp && iptest --coverage xml && cd -
         cp /tmp/ipy_coverage.xml ./
         cp /tmp/.coverage ./
     - name: pytest
       run: |
         pytest
     - name: Upload coverage to Codecov
       uses: codecov/codecov-action@v1