feat: add support for CommitStats

[olavloite]

Adds support for CommitStats to the JDBC driver.

[thiagotnunes]

LGTM

[skuruppu]

@olavloite I think we're almost ready to merge this. If you could please rebase and get it ready, that would be awesome.

[olavloite]

@olavloite I think we're almost ready to merge this. If you could please rebase and get it ready, that would be awesome.

This should now be ready to go once Spanner client version 4.0.3 is released.

[skuruppu]

@olavloite Spanner Client version 5.0 is released 🎉

[codecov]

Codecov Report

Merging #261 (8416ebe) into master (f0cdf11) will increase coverage by 0.16%.
The diff coverage is 85.71%.

@@             Coverage Diff              @@
##             master     #261      +/-   ##
============================================
+ Coverage     71.96%   72.13%   +0.16%     
- Complexity     1132     1136       +4     
============================================
  Files            24       24              
  Lines          3524     3538      +14     
  Branches        539      539              
============================================
+ Hits           2536     2552      +16     
+ Misses          769      767       -2     
  Partials        219      219              

Impacted Files	Coverage Δ	Complexity Δ
.../com/google/cloud/spanner/jdbc/JdbcConnection.java	48.43% <85.71%> (+4.41%)	46.00 <3.00> (+4.00)

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[olavloite]

@olavloite Spanner Client version 5.0 is released

@skuruppu It seems that we should not (cannot?) release this until Spanner 5.0.0 is included in the google-cloud-libraries-bom. The linkage monitor checks that the most recent versions in the bom are compatible with each other, and the current version of the bom contains Spanner 4.0.1 which is not compatible with this change.

[skuruppu]

@skuruppu It seems that we should not (cannot?) release this until Spanner 5.0.0 is included in the google-cloud-libraries-bom. The linkage monitor checks that the most recent versions in the bom are compatible with each other, and the current version of the bom contains Spanner 4.0.1 which is not compatible with this change.

Ah yikes ok, we'll have to request another BOM update then. @thiagotnunes would you be able to look into this?