chore: regenerate README (#383)

This PR was generated using Autosynth. 🌈


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

```
2020-12-14 20:05:00,785 synthtool [DEBUG] > Executing /root/.cache/synthtool/java-speech/.github/readme/synth.py.
On branch autosynth-readme
nothing to commit, working tree clean
2020-12-14 20:05:01,905 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/e67fc8c5-e470-470b-a446-e1015d65ebed/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-speech.git",
-        "sha": "9c5876f4445fce52941e4e8b83b92da7d6cbed1b"
+        "sha": "ce1d6f5187246891815d96bbb3dc5ea9b1efedc5"
       }
     },
     {

README.md

@@ -39,7 +39,7 @@ If you are using Maven without BOM, add this to your dependencies:
 <dependency>
   <groupId>com.google.cloud</groupId>
   <artifactId>google-cloud-speech</artifactId>
-  <version>1.24.7</version>
+  <version>1.24.8</version>
 </dependency>
 
 ```