This PR was generated using Autosynth. 🌈


<details><summary>Log from Synthtool</summary>

```
2020-12-14 12:56:30,153 synthtool [DEBUG] > Executing /root/.cache/synthtool/java-spanner/.github/readme/synth.py.
On branch autosynth-readme
nothing to commit, working tree clean
2020-12-14 12:56:31,121 synthtool [DEBUG] > Wrote metadata to .github/readme/synth.metadata/synth.metadata.

```
</details>

Full log will be available here:
https://source.cloud.google.com/results/invocations/32a7f03b-dcf8-4d69-b375-3e98baebaaa5/targets

- [ ] To automatically regenerate this PR, check this box.

This is an auto-generated regeneration of the .pb.go files by
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Corresponding google-cloud-go PR: googleapis/google-cloud-go#5297

Changes:

chore(deps): upgrade gapic-generator-java to 2.2.4
  PiperOrigin-RevId: 420055251
  Source-Link: googleapis/googleapis@76762cc

fix!(networksecurity): updating metadata messages for all long running operations
  This change might be breaking for client libraries in some languages.

  PiperOrigin-RevId: 419931787
  Source-Link: googleapis/googleapis@060a1d3

chore(bazel): update gapic-generator-go to v0.24.0
  Changes include:
  * make regapics more robust
  * add new compute module as dependency

  PiperOrigin-RevId: 419925076
  Source-Link: googleapis/googleapis@79493b1

feat(datastore/admin): define Datastore -> Firestore in Datastore mode migration long running operation metadata
  PiperOrigin-RevId: 419875388
  Source-Link: googleapis/googleapis@1236b08

feat: Update gapic-generator-php to v1.3.0
  Changes include:

  - diregapic: generate string constants for enum names
  - bazel: update composer to version 2.1.14 from 2.1.5

  PiperOrigin-RevId: 419853091
  Source-Link: googleapis/googleapis@82c132f

chore: regenerate API index

  Source-Link: googleapis/googleapis@2c1ea17

* feat: add support for PostgreSQL dialect

* fix: address review comments

* deps: bump java-spanner to 6.19.1

* feat: support automatic dialect detection

* deps: remove threeten + add gax

* build: use owned instance for integration tests

* build: use same instance as the client library

🤖 I have created a release *beep* *boop*
---


## [2.6.0](googleapis/java-spanner-jdbc@v2.5.11...v2.6.0) (2022-02-24)


### Features

* add support for PostgreSQL dialect ([googleapis#739](googleapis/java-spanner-jdbc#739)) ([f9daa19](googleapis/java-spanner-jdbc@f9daa19))


### Bug Fixes

* create specific metadata queries for PG ([googleapis#759](googleapis/java-spanner-jdbc#759)) ([caffda0](googleapis/java-spanner-jdbc@caffda0))


### Dependencies

* update dependency com.google.cloud:google-cloud-spanner-bom to v6.20.0 ([googleapis#758](googleapis/java-spanner-jdbc#758)) ([311d1ca](googleapis/java-spanner-jdbc@311d1ca))

---
This PR was generated with [Release Please](https://github.com/googleapis/release-please). See [documentation](https://github.com/googleapis/release-please#release-please).