connectapi 0.12.0

• Apps running on Connect Cloud are now supported for OAuth integrations via the
  new on_connect_cloud() helper. The POSIT_PRODUCT environment variable is
  now recognized as an alternative to RSTUDIO_PRODUCT for detecting Connect
  (#522).
• When using integrations, prefer to read from
  CONNECT_CONTENT_SESSION_TOKEN_FILE to find the session token. This helps
  long-running processes ensure that they can maintain fresh credentials (#518).