chore: regenerate README (#566)

This PR was generated using Autosynth. 🌈


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

```
2020-12-11 19:54:11,434 synthtool [DEBUG] > Executing /root/.cache/synthtool/java-bigquerydatatransfer/.github/readme/synth.py.
On branch autosynth-readme
nothing to commit, working tree clean
2020-12-11 19:54:12,302 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/686f2d1d-f7d4-4e76-b85d-a7dc77346c0d/targets

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

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

@@ -4,14 +4,14 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-bigquerydatatransfer.git",
-        "sha": "93bd73ff8928255b19b70a30581f7339d3f484d8"
+        "sha": "9124299172aa7d2c4e89527447b4ebbf4818a77e"
       }
     },
     {
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "3559dd8cb634347737632776ef4089443eacdb4f"
+        "sha": "996775eca5fd934edac3c2ae34b80ff0395b1717"
       }
     }
   ]

README.md

@@ -162,6 +162,8 @@ Java 8 OSX | [![Kokoro CI][kokoro-badge-image-3]][kokoro-badge-link-3]
 Java 8 Windows | [![Kokoro CI][kokoro-badge-image-4]][kokoro-badge-link-4]
 Java 11 | [![Kokoro CI][kokoro-badge-image-5]][kokoro-badge-link-5]
 
+Java is a registered trademark of Oracle and/or its affiliates.
+
 [product-docs]: https://cloud.google.com/bigquery/transfer/
 [javadocs]: https://googleapis.dev/java/google-cloud-bigquerydatatransfer/latest
 [kokoro-badge-image-1]: http://storage.googleapis.com/cloud-devrel-public/java/badges/java-bigquerydatatransfer/java7.svg