feat: add support for Hive partitioning options when creating external tables

[ekanth]

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Fixes #235 ☕️

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[ekanth]

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[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (master@6213ea9). Click here to learn what that means.
The diff coverage is 53.33%.

@@ Coverage Diff @@ ## master #236 +/- ## ========================================= Coverage ? 77.53% Complexity ? 1151 ========================================= Files ? 75 Lines ? 6089 Branches ? 654 ========================================= Hits ? 4721 Misses ? 1019 Partials ? 349

Impacted Files	Coverage Δ	Complexity Δ
...google/cloud/bigquery/HivePartitioningOptions.java	83.78% <20%> (ø)	11 <2> (?)
...google/cloud/bigquery/ExternalTableDefinition.java	57.69% <70%> (ø)	19 <1> (?)

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[stephaniewang526]

this breaks binary compatibility

[ekanth]

Thanks @stephaniewang526 for the review. I will update the patch and send again.

[ekanth]

@stephaniewang526, @pmakani I updated the patch and I wonder if the tests would automatically run?

[ekanth]

@stephaniewang526, thanks for triggering the tests. It was my bad with the previous patch - I missed a line that I fixed locally related to the test failures. Could you please trigger the tests again?

[ekanth]

Thanks @stephaniewang526. All tests passed now.

[stephaniewang526]

In general, when you make a commit please be sure to:

1. make initial commit message in the format - "feat: blah blah..." (note that "blah" has a space in front of the colon and is in lowercase)

2. run maven coveo code formatter so that code format is correct: mvn com.coveo:fmt-maven-plugin:format

3. check and make sure all builds succeed and correct any build failures. In this case, abstract classes were added which break binary compatibility --

[ERROR] 7013: com.google.cloud.bigquery.ExternalTableDefinition: Abstract method 'public com.google.cloud.bigquery.HivePartitioningOptions getHivePartitioningOptions()' has been added [ERROR] 7013: com.google.cloud.bigquery.ExternalTableDefinition$Builder: Abstract method 'public com.google.cloud.bigquery.ExternalTableDefinition$Builder setHivePartitioningOptions(com.google.cloud.bigquery.HivePartitioningOptions)' has been added 

we don't want to do this because this renders our client unstable and would break customer's existing implementation. I suggest to try either implement without abstract and add default implementation or encapsulate with an inner method.

[stephaniewang526]

this breaks binary compatibility