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Description of the Change

The command git push origin master is failing in our nightly action, because the local repository available from a schedule trigger has no master ref:

check run

ℹ  info      Fetching the latest GraphQL schema changes.
ℹ  info      Committing schema changes.
ℹ  info      Re-running relay compiler.
ℹ  info      Relay output:

Writing js
Unchanged: 62 files
ℹ  info      Generated relay files are unchanged.
✖  fatal     Error: Command failed: git push origin master 
error: src refspec master does not match any.
error: failed to push some refs to 'https://github.com/atom/github.git'


    at makeError (/node_modules/execa/index.js:174:9)
    at Promise.all.then.arr (/node_modules/execa/index.js:278:16)
    at <anonymous>
    at process._tickCallback (internal/process/next_tick.js:189:7)

I've changed it to default to a full refspec that should work as long as we have a repo:

git push origin HEAD:refs/heads/master

I've also bumped the schedule to try again tonight.

Screenshot/Gif

N/A

Alternate Designs

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Benefits

Another iteration closer to the GitHub action introduced in #2108 working properly.

Possible Drawbacks

N/A

Applicable Issues

N/A

Metrics

N/A

Tests

Documentation

N/A

Release Notes

N/A

User Experience Research (Optional)

N/A