chore: regenerate README (#545)

This PR was generated using Autosynth. 🌈


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

```
2021-06-03 15:31:33,863 synthtool [DEBUG] > Executing /root/.cache/synthtool/java-datacatalog/.github/readme/synth.py.
On branch autosynth-readme
nothing to commit, working tree clean
2021-06-03 15:31:35,257 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/ed26d34d-0e6c-4b2f-92da-760e210ed5b3/targets

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

@@ -4,14 +4,14 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-datacatalog.git",
-        "sha": "db9ed5b5e5472dae63e33058134bf8d2287cf4ad"
+        "sha": "97b9c8d1422db3c4077938af1496f70a61dc9bad"
       }
     },
     {
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "c3e41da0fa256ad7f6b4bc76b9d069dedecdfef4"
+        "sha": "811d20bc0b00c09773dfc74ac2baaf1286e943b7"
       }
     }
   ]

README.md

@@ -38,7 +38,7 @@ If you are using Maven without BOM, add this to your dependencies:
 <dependency>
   <groupId>com.google.cloud</groupId>
   <artifactId>google-cloud-datacatalog</artifactId>
-  <version>1.3.3</version>
+  <version>1.4.0</version>
 </dependency>
 
 ```
@@ -51,12 +51,12 @@ compile 'com.google.cloud:google-cloud-datacatalog'
 ```
 If you are using Gradle without BOM, add this to your dependencies
 ```Groovy
-compile 'com.google.cloud:google-cloud-datacatalog:1.3.3'
+compile 'com.google.cloud:google-cloud-datacatalog:1.4.0'
 ```
 
 If you are using SBT, add this to your dependencies
 ```Scala
-libraryDependencies += "com.google.cloud" % "google-cloud-datacatalog" % "1.3.3"
+libraryDependencies += "com.google.cloud" % "google-cloud-datacatalog" % "1.4.0"
 ```
 
 ## Authentication