fix(deps): Update junit to v6 (major) (#380)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [org.junit.jupiter:junit-jupiter-api](https://junit.org/) ([source](https://redirect.github.com/junit-team/junit-framework)) | dependencies | major | `5.11.4` -> `6.0.0` |
| [org.junit.jupiter:junit-jupiter](https://junit.org/) ([source](https://redirect.github.com/junit-team/junit-framework)) | dependencies | major | `5.11.4` -> `6.0.0` |
| [org.junit:junit-bom](https://junit.org/) ([source](https://redirect.github.com/junit-team/junit-framework)) | dependencies | major | `5.11.4` -> `6.0.0` |

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Author: cq-bot

lib/build.gradle

@@ -46,9 +46,9 @@ dependencies {
 
     testImplementation 'io.grpc:grpc-testing:1.75.0'
     testImplementation 'io.grpc:grpc-inprocess:1.75.0'
-    testImplementation platform('org.junit:junit-bom:5.13.4')
-    testImplementation 'org.junit.jupiter:junit-jupiter:5.13.4'
-    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.13.4'
+    testImplementation platform('org.junit:junit-bom:6.0.0')
+    testImplementation 'org.junit.jupiter:junit-jupiter:6.0.0'
+    testImplementation 'org.junit.jupiter:junit-jupiter-api:6.0.0'
     testImplementation 'org.mockito:mockito-core:5.20.0'
     testImplementation 'org.mockito:mockito-junit-jupiter:5.20.0'
     testImplementation 'nl.jqno.equalsverifier:equalsverifier:4.1.1'