Issue: Patch Operation on a group is removing all the users and groups

[de-jaina]

Description:

I was trying to use the patch_dbgroup method to patch the Databricks group from the Active directory, but it is removing all the members from that group instead of removing the selected members.

To Replicate:

1. Create a group in AAD.
2. Add 2 members in the group in AAD.
3. Execute the code. It will sync the Group and the members from AAD to Databricks Account.
4. Remove one member from the group in AAD.
5. Execute the code again to sync, but this time the group get empty. All the members from the group are getting removed.

What I tried:

I tried changing the schema to urn:ietf:params:scim:api:messages:2.0:PatchOp by referring databricks api doc for Azure, but it still does not work.

Also, I found one documentation from databricks that states: Group membership cannot be updated through PATCH/PUT requests.

### Other Issue:
There is a minor issue in the databricks_client.py file:
obj["value"] = member["value"]
UnboundLocalError: local variable 'obj' referenced before assignment

obj = dict() is missing at line no. 131.

@mick2004 , @AbhiDatabricks

[mick2004]

Thanks @de-jaina I will have a look on this coming weekend.Feel free to open a pr if you wish .

[mick2004]

@all-contributors please add @jaina15 for test

[allcontributors]

@mick2004

I've put up a pull request to add @jaina15! 🎉

[mick2004]

@all-contributors please add @jaina15 for test

[mick2004]

Fixed as part of 0826ba8 . new release 0.1.4 released