fix: add schema update back to json writer

[yirutang]

1. Add schema update back to json writer by recreate the stream.
2. Remove the batching support on json writer so that potentially it can be moved to use StreamWriterV2. This is to avoid users become dependent on the feature. Currently the move is not possible because StreamWriterV2 is lacking the schema update callback feature. It can probably be done inside json writer as well, but will do this later.
3. Also remove RetrySetting ExecutorSetting to be more consistent with what we actual support right now.

[codecov]

Codecov Report

Merging #905 (5e1f092) into master (7c1bb12) will increase coverage by 0.32%.
The diff coverage is 72.50%.

@@             Coverage Diff              @@
##             master     #905      +/-   ##
============================================
+ Coverage     80.38%   80.70%   +0.32%     
- Complexity     1015     1020       +5     
============================================
  Files            76       76              
  Lines          5576     5550      -26     
  Branches        436      410      -26     
============================================
- Hits           4482     4479       -3     
+ Misses          916      882      -34     
- Partials        178      189      +11     

Impacted Files	Coverage Δ	Complexity Δ
...oud/bigquery/storage/v1beta2/JsonStreamWriter.java	76.52% <63.15%> (+10.97%)	14.00 <0.00> (+2.00)
...e/cloud/bigquery/storage/v1beta2/StreamWriter.java	82.79% <80.95%> (+3.58%)	32.00 <0.00> (+1.00)
...bigquery/storage/v1alpha2/BigQueryWriteClient.java	74.02% <0.00%> (-6.50%)	38.00% <0.00%> (ø%)
.../bigquery/storage/v1beta2/BigQueryWriteClient.java	70.76% <0.00%> (-4.62%)	33.00% <0.00%> (ø%)
...ud/bigquery/storage/v1/BaseBigQueryReadClient.java	58.53% <0.00%> (-2.44%)	12.00% <0.00%> (ø%)
...gquery/storage/v1beta2/BaseBigQueryReadClient.java	58.53% <0.00%> (-2.44%)	12.00% <0.00%> (ø%)
...ery/storage/v1beta1/BaseBigQueryStorageClient.java	71.18% <0.00%> (-1.70%)	22.00% <0.00%> (ø%)
.../cloud/bigquery/storage/v1alpha2/StreamWriter.java	79.95% <0.00%> (-0.44%)	34.00% <0.00%> (ø%)
...cloud/bigquery/storage/v1beta2/StreamWriterV2.java	95.67% <0.00%> (-0.44%)	39.00% <0.00%> (ø%)
... and 2 more

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