orb(react-native-mlkit): chore: add ci:trust script to allow us to ru…

…n ci pipeline on forks (#148 by @trevor-coleman) (78f30eb3b9fcb51a366968a879d0758d2b1d5e8f)

docs/react-native-mlkit/contributing/running-tests-on-untrusted-forks.md

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+---
+name: Running Tests on Untrusted Forks
+sidebar_position: 99
+---
+
+# Running CI Scripts on Untrusted Forks
+
+Untrusted forks could contain malicious code to mine cryptocurrency, steal secrets, or otherwise harm the CI server.
+
+For PRs from untrusted forks, to run the CI scripts, we need to:
+
+1. Review the code to ensure that it is safe to run on the CI server.
+2. If the code is safe, run the `ci:trust` script to push the commits to a branch on the main repository, where the CI
+   scripts can be run.
+3. Once the tests have run, the status of the PR will be updated automatically (because the commits are the same).
+
+## How to run the CI scripts on untrusted forks:
+
+1. Copy the name of the branch from the PR.
+   <img src="./images/ci-copy-fork-branch.png" alt="ci-copy-fork-branch" width="400"/>
+2. From your local clone of the main repository, run the `ci:trust` script.
+    ```bash
+    yarn ci:trust <branch-name>
+    ```
+3. The branch will be pushed and the tests will run
+   <img src="./images/ci-tests-running.png" alt="ci-tests-running" width="400"/>
+
+## What does ci:trust do?
+
+The `ci:trust` script does the following:
+
+1. Adds and fetches the untrusted fork as a temporary remote in your local repository.
+2. Pushes the specific branch from the untrusted fork to a designated temporary branch in your original repository.
+3. Pushing to a local branch triggers the continuous integration (CI) tests on the commits of the branch.
+4. Because the commits are the same, the status of the PR will be updated automatically.
+
+### Notes
+
+1. The ci:trust script will only work if you have write access to the main repository. This prevents malicious users
+   from running the script on the main repository.
+2. The ci:trust script pushes the commits to a branch called `temp-branch-to-test-fork`.
+
+::: warning
+
+The `temp-branch-to-test-fork` branch will be deleted and recreated if it already exists. This allows the script to
+clean up its own temporary branches.
+
+:::