docs: Google Drive Loader always set the env var (#14791)
- **Description:** Code written by following, the official documentation
of [Google Drive
Loader](https://python.langchain.com/docs/integrations/document_loaders/google_drive),
gives errors. I have opened an issue regarding this. See #14725. This is
a pull request for modifying the documentation to use an approach that
makes the code work. Basically, the change is that we need to always set
the GOOGLE_APPLICATION_CREDENTIALS env var to an emtpy string, rather
than only in case of RefreshError. Also, rewrote 2 paragraphs to make
the instructions more clear.
- **Issue:** See this related [issue #
14725](https://github.com/langchain-ai/langchain/issues/14725)
- **Dependencies:** NA
- **Tag maintainer:** @baskaryan
- **Twitter handle:** NA
Co-authored-by: Snehil <snehil@example.com>
Co-authored-by: Bagatur <22008038+baskaryan@users.noreply.github.com>
