chore: regenerate README (#521)

This PR was generated using Autosynth. 🌈 <details><summary>Log from Synthtool</summary> ``` 2021-05-10 17:33:52,408 synthtool [DEBUG] > Executing /root/.cache/synthtool/java-trace/.github/readme/synth.py. On branch autosynth-readme nothing to commit, working tree clean 2021-05-10 17:33:53,543 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/2c711107-86a8-4eba-928e-fce04551c154/targets - [ ] To automatically regenerate this PR, check this box. (May take up to 24 hours.)

Author: yoshi-automation

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

@@ -4,14 +4,14 @@
  "git": {
  "name": ".",
  "remote": "https://github.com/googleapis/java-trace.git",
- "sha": "fd31b650ece208c539d3473745dcd77fe5c8f103"
+ "sha": "2973ea1b58f4bab53bd7ab96712e190d9ae1c49f"
  }
  },
  {
  "git": {
  "name": "synthtool",
  "remote": "https://github.com/googleapis/synthtool.git",
- "sha": "06a8cd0ff7e81b05e6c503eab510ec622384caa7"
+ "sha": "6726988c677bb78385868bfc48dbfa2fe981d44a"
  }
  }
  ]

README.md

@@ -45,7 +45,7 @@ If you are using Maven without BOM, add this to your dependencies:
 
 If you are using Gradle 5.x or later, add this to your dependencies
 ```Groovy
-implementation platform('com.google.cloud:libraries-bom:20.2.0')
+implementation platform('com.google.cloud:libraries-bom:20.3.0')
 
 compile 'com.google.cloud:google-cloud-trace'
 ```