chore: regenerate README (#466)

This PR was generated using Autosynth. 🌈


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

```
2020-10-24 08:10:17,743 synthtool [DEBUG] > Executing /root/.cache/synthtool/java-bigquerydatatransfer/.github/readme/synth.py.
On branch autosynth-readme
nothing to commit, working directory clean
2020-10-24 08:10:18,685 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/b7ddac5a-eed8-4ed2-89f2-cfdbadf12b22/targets

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

@@ -4,14 +4,14 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-bigquerydatatransfer.git",
-        "sha": "4ac277855d8062cc7432d9bf3a4d3dcc35e35c09"
+        "sha": "6eca0b4f2ac361dc3512eb803cc6209e795b8e5f"
       }
     },
     {
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "721a7d2abb129029eca9d85a40da6eb7b8b1739a"
+        "sha": "a783321fd55f010709294455584a553f4b24b944"
       }
     }
   ]

README.md

@@ -45,11 +45,11 @@ If you are using Maven without BOM, add this to your dependencies:
 
 If you are using Gradle, add this to your dependencies
 ```Groovy
-compile 'com.google.cloud:google-cloud-bigquerydatatransfer:1.0.14'
+compile 'com.google.cloud:google-cloud-bigquerydatatransfer:1.0.15'
 ```
 If you are using SBT, add this to your dependencies
 ```Scala
-libraryDependencies += "com.google.cloud" % "google-cloud-bigquerydatatransfer" % "1.0.14"
+libraryDependencies += "com.google.cloud" % "google-cloud-bigquerydatatransfer" % "1.0.15"
 ```
 
 ## Authentication