minor #838 [CI] run CI at least once per day (jrushlow)

This PR was merged into the 1.0-dev branch.

Discussion
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[CI] run CI at least once per day

Having a scheduled CI run will make it easier to track down upstream stream breaking changes. Especially when we don't have any push activity for days on end.

As a side effect, this will also give us better insight into the state of the Symfony eco-system as a whole as maker bundle tests just about every Symfony package in a simulated "real life" application.

Commits
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48ff67f [CI] run CI at least once per day

.github/workflows/ci.yaml

@@ -5,6 +5,8 @@ on:
     push:
         branches:
             - 'main'
+    schedule:
+        -   cron: '0 0 * * *'
 
 env:
     PHPUNIT_FLAGS: "-v"