Running on "push" event instead of pull_request

[edno]

Describe the bug
After setting up a new repo (private), I am not able to get Danger running (I am using a copy of a dangerfile.js that is working on existing repo).
The error is Unable to evaluate the Dangerfile TypeError: danger.git.fileMatch is not a function (see Debug trace).

When run locally using yarn danger local -b main --text-only then no error occured. The checks are performed as expected.

To Reproduce
Steps to reproduce the behavior:

1. Setup a new gh repo with a simple dangerfile eg const dangerFile = danger.git.fileMatch(DANGER_FILE);
2. Setup a gh action running danger DEBUG="*" yarn danger ci -b main --text-only

Expected behavior
No failure expected.

Debug trace

Run DEBUG="*" yarn danger ci -b main --text-only
2021-02-17T19:33:49.432Z danger:process_runner Debug mode on for Danger v10.6.2
2021-02-17T19:33:49.434Z danger:process_runner Starting sub-process run
2021-02-17T19:33:49.442Z danger:process_runner {
  dangerJSONDSL: {
    git: {
      commits: [],
      created_files: [],
      deleted_files: [],
      modified_files: []
    },
    github: {},
    settings: { github: [Object], cliArgs: [Object] }
  }
}
2021-02-17T19:33:49.442Z danger:process_runner Preparing to run: /opt/hostedtoolcache/node/12.20.2/x64/bin/node,/home/runner/work/live-platform-dataset/live-platform-dataset/.yarn/cache/danger-npm-10.6.2-bd26b96131-2ac6b50d29.zip/node_modules/danger/distribution/commands/danger-runner.js,-b,main,--text-only
2021-02-17T19:33:49.442Z danger:runDangerSubprocess Running sub-process: node - /home/runner/work/live-platform-dataset/live-platform-dataset/.yarn/cache/danger-npm-10.6.2-bd26b96131-2ac6b50d29.zip/node_modules/danger/distribution/commands/danger-runner.js,-b,main,--text-only
2021-02-17T19:33:49.450Z danger:runDangerSubprocess Started passing in STDIN
2021-02-17T19:33:49.451Z danger:runDangerSubprocess Passed DSL in via STDIN
2021-02-17T19:33:50.176Z danger:runner Started Danger runner with 

2021-02-17T19:33:50.183Z danger:runner Got STDIN for Danger Run

2021-02-17T19:33:50.185Z danger:jsonToDSL Creating event DSL from JSON

2021-02-17T19:33:50.205Z danger:runner Evaluating dangerfile.js

2021-02-17T19:33:50.212Z danger:transpiler:setup Does not have Babel set up

2021-02-17T19:33:50.212Z danger:inline_runner Started parsing Dangerfile:  dangerfile.js

Unable to evaluate the Dangerfile
 TypeError: danger.git.fileMatch is not a function

Environment

software	version
danger.js	10.6.2
node	12
yarn	2
Operating System	ubuntu-20.04

Additional context
Github workflow

name: Check branch

on: push

jobs:
  checks:
    name: Run branch checks
    runs-on: ubuntu-20.04

    steps:
    - name: Checkout
      uses: actions/checkout@v2

    - name: Setup Node.js
      uses: actions/setup-node@v2
      with:
        node-version: '12'

    - name: Yarn
      run: yarn install --immutable --immutable-cache

    - name: Danger
      run: DEBUG="*" yarn danger ci -b main --text-only
      env: 
        GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

    - name: Lint code
      run: yarn lint

    - name: Unit tests
      run: yarn test

[orta]

You're running on a push event, so there's no pull request metadata (which adds 'git') - I'd be open to adding support for Danger to try get some useful metadata from the push event to fill out the git