chore: regenerate README (#92)

This PR was generated using Autosynth. 🌈


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

```
2021-03-02 01:09:24,771 synthtool [DEBUG] > Executing /root/.cache/synthtool/java-pubsublite-kafka/.github/readme/synth.py.
On branch autosynth-readme
nothing to commit, working tree clean
2021-03-02 01:09:26,337 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/4423eaae-5653-49b2-8e8f-b0757f50f68e/targets

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

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

@@ -4,7 +4,7 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-pubsublite-kafka.git",
-        "sha": "c1cf1d1ff5d44d67219da61bb85120774bb6a724"
+        "sha": "cba8a24e693b559063b3b4ecbb8a27c26ff00c2f"
       }
     },
     {

README.md

@@ -20,18 +20,18 @@ If you are using Maven, add this to your pom.xml file:
 <dependency>
   <groupId>com.google.cloud</groupId>
   <artifactId>pubsublite-kafka</artifactId>
-  <version>0.2.0</version>
+  <version>0.2.1</version>
 </dependency>
 ```
 
 If you are using Gradle without BOM, add this to your dependencies
 ```Groovy
-compile 'com.google.cloud:pubsublite-kafka:0.2.0'
+compile 'com.google.cloud:pubsublite-kafka:0.2.1'
 ```
 
 If you are using SBT, add this to your dependencies
 ```Scala
-libraryDependencies += "com.google.cloud" % "pubsublite-kafka" % "0.2.0"
+libraryDependencies += "com.google.cloud" % "pubsublite-kafka" % "0.2.1"
 ```
 
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