chore(deps): update dependency com.google.cloud:google-cloud-asset to v1.4.0 (GoogleCloudPlatform#3219)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [com.google.cloud:google-cloud-asset](https://togithub.com/googleapis/java-asset) | minor | `1.3.0` -> `1.4.0` |

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### Release Notes

<details>
<summary>googleapis/java-asset</summary>

### [`v1.4.0`](https://togithub.com/googleapis/java-asset/blob/master/CHANGELOG.md#&#8203;140-httpswwwgithubcomgoogleapisjava-assetcomparev130v140-2020-06-22)

[Compare Source](https://togithub.com/googleapis/java-asset/compare/v1.3.0...v1.4.0)

##### Features

-   **deps:** adopt flatten plugin and google-cloud-shared-dependencies ([#&GoogleCloudPlatform#8203;220](https://www.github.com/googleapis/java-asset/issues/220)) ([504f871](https://www.github.com/googleapis/java-asset/commit/504f871bbf7fc847eeab37eaa9c1836e2a3af994))
-   **v1:** add condition to Feed ([#&GoogleCloudPlatform#8203;226](https://www.github.com/googleapis/java-asset/issues/226)) ([f14bd11](https://www.github.com/googleapis/java-asset/commit/f14bd119c952bd38bf03fd25a98e8bc4641b84fe))

</details>

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asset/cloud-client/pom.xml

@@ -35,7 +35,7 @@
     <dependency>
       <groupId>com.google.cloud</groupId>
       <artifactId>google-cloud-asset</artifactId>
-      <version>1.3.0</version>
+      <version>1.4.0</version>
     </dependency>
     <!-- [END asset_java_dependencies] -->