chore: regenerate README (#751)

This PR was generated using Autosynth. 🌈


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

```
2021-03-09 20:47:34,815 synthtool [DEBUG] > Executing /root/.cache/synthtool/java-storage/.github/readme/synth.py.
On branch autosynth-readme
nothing to commit, working tree clean
2021-03-09 20:47:35,664 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/935f8f31-d7ea-4a0f-bf2f-d793400d62f5/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-storage.git",
-        "sha": "bac66b212117b0586d100467aa840e4358b4ba84"
+        "sha": "bb42107ff10148e14e112ff78534753f2ebc7dd9"
       }
     },
     {
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "2e7bd5cc66a3f0b90ce1c150eb35c89eeb9872d6"
+        "sha": "e5fa6d93e42918dd4a000a80b92be23f5f4c6ac7"
       }
     }
   ]

README.md

@@ -51,12 +51,12 @@ compile 'com.google.cloud:google-cloud-storage'
 ```
 If you are using Gradle without BOM, add this to your dependencies
 ```Groovy
-compile 'com.google.cloud:google-cloud-storage:1.113.12'
+compile 'com.google.cloud:google-cloud-storage:1.113.13'
 ```
 
 If you are using SBT, add this to your dependencies
 ```Scala
-libraryDependencies += "com.google.cloud" % "google-cloud-storage" % "1.113.12"
+libraryDependencies += "com.google.cloud" % "google-cloud-storage" % "1.113.13"
 ```
 
 ## Authentication