chore: enable gapic v2 and proto annotation for automl API.

[yoshi-automation]

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[codecov]

Codecov Report

Merging #156 into master will decrease coverage by 0.19%.
The diff coverage is 80.71%.

@@             Coverage Diff              @@
##             master     #156      +/-   ##
============================================
- Coverage     77.02%   76.82%   -0.20%     
- Complexity      351      354       +3     
============================================
  Files            24       24              
  Lines          3338     3362      +24     
  Branches         12       12              
============================================
+ Hits           2571     2583      +12     
- Misses          717      726       +9     
- Partials         50       53       +3     

Impacted Files	Coverage Δ	Complexity Δ
...ava/com/google/cloud/automl/v1/AutoMlSettings.java	8.64% <0.00%> (ø)	2.00 <0.00> (ø)
...va/com/google/cloud/automl/v1/stub/AutoMlStub.java	3.12% <0.00%> (ø)	1.00 <0.00> (ø)
.../com/google/cloud/automl/v1beta1/AutoMlClient.java	64.82% <ø> (-1.11%)	75.00 <0.00> (+2.00)	⬇️
...om/google/cloud/automl/v1beta1/AutoMlSettings.java	7.52% <0.00%> (ø)	2.00 <0.00> (ø)
.../cloud/automl/v1beta1/PredictionServiceClient.java	44.23% <ø> (ø)	9.00 <0.00> (ø)
...m/google/cloud/automl/v1beta1/stub/AutoMlStub.java	2.50% <0.00%> (ø)	1.00 <0.00> (ø)
.../java/com/google/cloud/automl/v1/AutoMlClient.java	62.44% <62.06%> (-0.19%)	57.00 <13.00> (+1.00)	⬇️
.../cloud/automl/v1beta1/stub/AutoMlStubSettings.java	87.56% <81.36%> (ø)	42.00 <13.00> (ø)
...oogle/cloud/automl/v1/stub/AutoMlStubSettings.java	88.78% <90.32%> (ø)	36.00 <6.00> (ø)
...om/google/cloud/automl/v1/stub/GrpcAutoMlStub.java	95.03% <97.01%> (ø)	25.00 <5.00> (ø)
... and 5 more

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