chore: regenerate README (#568)

This PR was generated using Autosynth. 🌈


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

```
2021-06-16 18:00:20,526 synthtool [DEBUG] > Executing /root/.cache/synthtool/java-video-intelligence/.github/readme/synth.py.
On branch autosynth-readme
nothing to commit, working tree clean
2021-06-16 18:00:21,840 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/4f0820ab-9a52-43a0-8a99-341d6d0b3760/targets

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

@@ -4,14 +4,14 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-video-intelligence.git",
-        "sha": "a7c538a6a79b268dfbb0a566b36de504cd89e87a"
+        "sha": "16c4ef8a2e9037c8493c397055bc09434f1311c1"
       }
     },
     {
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "5cae043787729a908ed0cab28ca27baf9acee3c4"
+        "sha": "8f76a885deaaf2fe234daeba4a8cc4d1b3de8086"
       }
     }
   ]

README.md

@@ -60,12 +60,12 @@ compile 'com.google.cloud:google-cloud-video-intelligence'
 ```
 If you are using Gradle without BOM, add this to your dependencies
 ```Groovy
-compile 'com.google.cloud:google-cloud-video-intelligence:1.7.2'
+compile 'com.google.cloud:google-cloud-video-intelligence:1.7.3'
 ```
 
 If you are using SBT, add this to your dependencies
 ```Scala
-libraryDependencies += "com.google.cloud" % "google-cloud-video-intelligence" % "1.7.2"
+libraryDependencies += "com.google.cloud" % "google-cloud-video-intelligence" % "1.7.3"
 ```
 
 ## Authentication