feature: Added support for Google cloud log sink management via google provider

[arvindp25]

---

Issues/feature request link: #51929
This pull request introduces new operator in google provider.
With help of new operator airflow user now can create google cloud log sinks via airflow.

### Checklist

- [x] Unit tests added
- [x] System test added
- [x] Documentation updated (docstrings + relevant .rst files if applicable)
- [x] PR description includes motivation and usage example
- [x] Follows Airflow’s [contribution guidelines](https://github.com/apache/airflow/blob/main/CONTRIBUTING.rst)

^ Add meaningful description above
Read the Pull Request Guidelines for more information.
In case of fundamental code changes, an Airflow Improvement Proposal (AIP) is needed.
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In case of backwards incompatible changes please leave a note in a newsfragment file, named {pr_number}.significant.rst or {issue_number}.significant.rst, in airflow-core/newsfragments.

[boring-cyborg]

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[shahar1]

Looks promising overall! Small comment regarding validation of templated fields.
@VladaZakharova - I'll be happy for additional feedback :)

[VladaZakharova]

Hi
can you please show system tests results with screenshots? thanks

[arvindp25]

Hi can you please show system tests results with screenshots? thanks
@VladaZakharova
for system test, I have recorded video please fast forward as per your need.

video.mp4

further below I have added some additional screenshot from manual dag testing.

creating multiple log sink with different destination

updating log sink

list sink

delete sinks

Please let me know if i have to do something else as Proof of work.
thanks,

[shahar1]

LGTM, well done!
Waiting for @VladaZakharova 's approval to merge :)

[arvindp25]

System Test:-
video
https://github.com/user-attachments/assets/01fce6e2-cc4f-4d11-b8c7-b1d06b61a47e

unit test hook:-

unit test operator:-

manual dag testing:-
creating sink ✅

test_bq_sink and test_pubsub_sink got created.

update_sink ✅
my-airflow-test-sink updated successfully.

list sink ✅
total number of sink on project 5 can be matched in log output

delete_sink ✅
all three sink got deleted.

[arvindp25]

@VladaZakharova I have made requested change. Could you please re-review?
change:-
1.moved connection logic to hook
2. used sink_config for configuration support both dict and protobuf obj
3. removed example_ from dag names

Added:-
protobuf support.
system test with protobuf object.

[VladaZakharova]

Looks good, small comments left 😺

[arvindp25]

@VladaZakharova made requested change. Please check

[arvindp25]

@VladaZakharova Just a friendly reminder to look at this.

[VladaZakharova]

Good job!