message: Update fetch-tool documentation
diff: Connection using ODSP or routerlicious driver to dump the messages or snapshot information on the server.
  In order to connect to ODSP, the clientID and clientSecret must be set as environment variables login__microsoft__clientId and login__microsoft__secret, respectively. If you have access to the keyvault this can be done by running [this tool](../../../tools/getkeys).
  +Beware that to use fetch-tool on documents in the Microsoft tenant, you will need to follow the fetch tool usage instructions on the "Debugging Tools" page of the internal Fluid wiki.
  ## Usage
  