fix: pass --project-path option when uploading JS sourcemaps to Datadog

[adamstankiewicz]

Starting upload with concurrency 20. 
Will look for sourcemaps in target/dist
Will match JS files for errors on files starting with /
version: b533813f29e4221ab3b48c51b55c5f9710776118 service: edx-frontend-app-learner-portal-enterprise project path: 

Command summary:
⚠️ No sourcemaps detected. Did you specify the correct directory?
b'Deploy frontend: Uploading source maps to Datadog for app frontend-app-learner-portal-enterprise.'

When attempting an MFE deployment, datadog-ci is failing to detect JS source maps in the dist directory. This PR attempts to resolve by providing the --project-path command arg to datadog-ci per the Datadog documentation:

When looking at the sourcemaps generated by @openedx/frontend-build, the file paths do seem to reference a prefix of the app name. Example:

{
  "sources": [
    "webpack://frontend-app-learner-portal-enterprise/./src/components/integration-warning-modal/ModalBody.jsx"
  ],
}

This PR attempts to see if sourcemaps can be detected by providing the `f'--project-path="{self.app_name}/"', to the Datadog CLI command.