test(deps): update dependency junit:junit to v4.13.2 (#140)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [junit:junit](http://junit.org) ([source](https://github.com/junit-team/junit4)) | `4.13.1` -> `4.13.2` | [![age](https://badges.renovateapi.com/packages/maven/junit:junit/4.13.2/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/maven/junit:junit/4.13.2/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/maven/junit:junit/4.13.2/compatibility-slim/4.13.1)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/maven/junit:junit/4.13.2/confidence-slim/4.13.1)](https://docs.renovatebot.com/merge-confidence/) |

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google-cloud-dialogflow-cx/pom.xml

@@ -72,7 +72,7 @@
       <groupId>junit</groupId>
       <artifactId>junit</artifactId>
       <scope>test</scope>
-      <version>4.13.1</version>
+      <version>4.13.2</version>
     </dependency>
     <dependency>
       <groupId>com.google.cloud</groupId>

samples/install-without-bom/pom.xml

@@ -36,7 +36,7 @@
     <dependency>
       <groupId>junit</groupId>
       <artifactId>junit</artifactId>
-      <version>4.13.1</version>
+      <version>4.13.2</version>
       <scope>test</scope>
     </dependency>
     <dependency>

samples/snapshot/pom.xml

@@ -35,7 +35,7 @@
     <dependency>
       <groupId>junit</groupId>
       <artifactId>junit</artifactId>
-      <version>4.13.1</version>
+      <version>4.13.2</version>
       <scope>test</scope>
     </dependency>
     <dependency>

samples/snippets/pom.xml

@@ -34,7 +34,7 @@
     <dependency>
       <groupId>junit</groupId>
       <artifactId>junit</artifactId>
-      <version>4.13.1</version>
+      <version>4.13.2</version>
       <scope>test</scope>
     </dependency>
     <dependency>