release 0.7.2rc4 (#1402)

* instructions for changelog

* instructions for changelog

* on

.github/PULL_REQUEST_TEMPLATE.md

@@ -6,6 +6,8 @@
 - [ ] Did you write any new necessary tests?  
 - [ ] If you made a notable change (that affects users), did you update the [CHANGELOG](https://github.com/PyTorchLightning/pytorch-lightning/blob/master/.github/CHANGELOG.md)?
 
+<!-- For CHANGELOG separate each item in unreleased section by blank line to reduce collisions -->
+
 ## What does this PR do?
 Fixes # (issue).
 

.github/workflows/pypi-release.yml

@@ -1,16 +1,18 @@
 name: PyPI Release
 
-on: [push]
+# https://help.github.com/en/actions/reference/events-that-trigger-workflows
+on:
+  # Trigger the workflow on push or pull request,
+  # but only for the master branch
+  push:
+    branches:
+      - master
 
 # based on https://github.com/pypa/gh-action-pypi-publish
 
 jobs:
   build:
     runs-on: ubuntu-latest
-    strategy:
-      max-parallel: 4
-      matrix:
-        python-version: [3.6, 3.7]
 
     steps:
     - uses: actions/checkout@master

pytorch_lightning/__init__.py

@@ -1,6 +1,6 @@
 """Root package info."""
 
-__version__ = '0.7.2rc3'
+__version__ = '0.7.2rc4'
 __author__ = 'William Falcon et al.'
 __author_email__ = 'waf2107@columbia.edu'
 __license__ = 'Apache-2.0'