Sync-ics2gcal

What's Changed
* types
* python 3.9+
* docs https://github.com/b4tman/sync_ics2gcal/pull/204
* updated deps by dependabot

**Full Changelog**: https://github.com/b4tman/sync_ics2gcal/compare/v0.1.4...v0.1.5

- overwrite events without updated field (80 81)
- drop python 3.6 support
- add python 3.10 support
- format with black (88)

migrate to poetry

* type annotations
* fire instead of argparse
* drop python 3.5
* add python 3.9

* default credentials support (docs [here](https://googleapis.dev/python/google-auth/latest/reference/google.auth.html#google.auth.default) and [here](https://developers.google.com/identity/protocols/application-default-credentials) )
* README updated

first version!