anchor.diff:  
   | Variable                       | Description and source                                         |
   |--------------------------------|----------------------------------------------------------------|
  -| `BUILDKITE_ANALYTICS_KEY`      | Unique key for the build that initiated the Test Analytics run |
  +| `BUILDKITE_ANALYTICS_KEY`      | a unique key for the build that initiated the Test Analytics run |
   | `BUILDKITE_ANALYTICS_URL`      | URL that links to the build                                    |
   | `BUILDKITE_ANALYTICS_BRANCH`   | the branch or ref that this run is for                         |
  -| `BUILDKITE_ANALYTICS_SHA`      | the commit sha for the head of the branch                      |
  +| `BUILDKITE_ANALYTICS_SHA`      | the commit SHA for the head of the branch                      |
   | `BUILDKITE_ANALYTICS_NUMBER`   | the build number of the build                                  |
   | `BUILDKITE_ANALYTICS_JOB_ID`   | the id of a job within the build                               |
   | `BUILDKITE_ANANLYTICS_MESSAGE` | the commit message for the head of the branch                  |
  
positive.code: 
  | Variable     | Description and source                                                                                          |
  |--------------|-----------------------------------------------------------------------------------------------------------------|
  | `key`        | Unique key for the build that initiated the Test Analytics run<br />`CIRCLE_WORKFLOW_ID` and `CIRCLE_BUILD_NUM` |
  | `url`        | a URL that links to the build <br /> `CIRCLE_BUILD_URL`                                                         |
  | `branch`     | the branch or ref that this run is for<br />`CIRCLE_BRANCH`                                                     |
  | `commit_sha` | the commit sha for the head of the branch<br />`CIRCLE_SHA1`                                                    |
  | `number`     | the build number of the build<br />    `CIRCLE_BUILD_NUM`                                                       |
  
  To pass a human-readable commit message through to Test Analytics, set the `BUILDKITE_ANALYTICS_MESSAGE` variable.
  
negative.code: 
  | Variable     | Description                                                    |
  |--------------|----------------------------------------------------------------|
  | `key`        | a unique key for the build that initiated the Test Analytics run |
  | `url`        | URL that links to the build                                    |
  | `branch`     | the branch or ref that this run is for                         |
  | `commit_sha` | the commit SHA for the head of the branch                      |
  | `number`     | the build number of the build                                  |
  | `job_id`     | the id of a job within the build                               |
  | `message`    | the commit message for the head of the branch                  |
  