Allow BigQuery project to be configured

[MattDelac]

What this PR does / why we need it:
Add the possibility to specify a GCP project for the temporary datasets created.

For example, with the config file and a ServiceAccount coming from the project ml-adhoc

[...]
offline_store:
    type: bigquery
    project: ml-production

>>> from google.cloud import bigquery
>>>from feast.feature_store import FeatureStore
>>> store = FeatureStore()

>>> store.config.offline_store.project
'ml-production'

>>> bigquery.Client().project
'ml-adhoc'

Which means that the ServiceAccount ml-adhoc will write into the BQ project ml-production (names are just for examples)

Which issue(s) this PR fixes:

Fixes #1655

Does this PR introduce a user-facing change?:

NONE

Possibility to specify a different GCP project than the ServiceAccount to save the BigQuery tables

[feast-ci-bot]

Skipping CI for Draft Pull Request.
If you want CI signal for your change, please convert it to an actual PR.
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[codecov-commenter]

Codecov Report

Merging #1656 (6cde3a3) into master (a708915) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #1656   +/-   ##
=======================================
  Coverage   83.54%   83.54%           
=======================================
  Files          71       71           
  Lines        6173     6176    +3     
=======================================
+ Hits         5157     5160    +3     
  Misses       1016     1016           

Flag	Coverage Δ
integrationtests	83.46% <100.00%> (+<0.01%)	⬆️
unittests	76.22% <25.00%> (-0.03%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
sdk/python/feast/infra/offline_stores/bigquery.py	86.59% <100.00%> (+0.13%)	⬆️
sdk/python/feast/repo_config.py	95.93% <100.00%> (+0.03%)	⬆️

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[feast-ci-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: MattDelac, woop

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[woop]

/lgtm