chore: regenerate README (#648)

This PR was generated using Autosynth. 🌈 <details><summary>Log from Synthtool</summary> ``` 2020-11-18 00:20:16,991 synthtool [DEBUG] > Executing /root/.cache/synthtool/java-spanner/.github/readme/synth.py. On branch autosynth-readme nothing to commit, working directory clean 2020-11-18 00:20:17,985 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/44f2d200-ccfc-470d-8d23-b1d174cc7c25/targets - [ ] To automatically regenerate this PR, check this box.

Author: yoshi-automation

.github/readme/synth.metadata/synth.metadata

@@ -4,14 +4,14 @@
  "git": {
  "name": ".",
  "remote": "https://github.com/googleapis/java-spanner.git",
- "sha": "54de51438bac14c66e241fe68a341a47e641c5f2"
+ "sha": "447a99b9a6ccdfd3855505fca13e849fb9513943"
  }
  },
  {
  "git": {
  "name": "synthtool",
  "remote": "https://github.com/googleapis/synthtool.git",
- "sha": "d5fc0bcf9ea9789c5b0e3154a9e3b29e5cea6116"
+ "sha": "7fcc405a579d5d53a726ff3da1b7c8c08f0f2d58"
  }
  }
  ]

README.md

@@ -38,7 +38,7 @@ If you are using Maven without BOM, add this to your dependencies:
 <dependency>
  <groupId>com.google.cloud</groupId>
  <artifactId>google-cloud-spanner</artifactId>
- <version>3.0.3</version>
+ <version>3.0.4</version>
 </dependency>
 
 ```