Schedule GitHub workflows (#74)

Co-authored-by: Alexander Makarov <sam@rmcreative.ru>

Author: viktorprogger

.github/workflows/bc.yml

@@ -1,6 +1,8 @@
 on:
- - pull_request
- - push
+ pull_request:
+ push:
+ schedule:
+ - cron: '0 0 * * *'
 
 name: backwards compatibility
 jobs:

.github/workflows/mutation.yml

@@ -1,8 +1,6 @@
 on:
  pull_request:
  push:
- branches:
- - "master"
  schedule:
  - cron: '0 0 * * *'