fix: plugin with id 'spring-cloud-contract' not found error after bumping spring-cloud-contract-gradle-plugin version from 5.0.0 to 5.0.3.

- The shorthand spring-cloud-contract plugin ID was dropped between 5.0.0 and 5.0.1.
- Changed to use the full plugin id that exists in previous and current versions.

ai-assisted=yes
TNZ-114567

Author: hsinn0

applications/credhub-api/build.gradle

@@ -28,7 +28,7 @@ apply plugin: 'kotlin'
 apply plugin: 'kotlin-spring'
 apply plugin: 'org.springframework.boot'
 apply plugin: 'io.spring.dependency-management'
-apply plugin: 'spring-cloud-contract'
+apply plugin: 'org.springframework.cloud.contract'
 apply from: "${rootDir.toPath()}/spring-cloud-contract-config.gradle"
 apply from: "${rootDir.toPath()}/kotlin.gradle"
 apply from: "${rootDir.toPath()}/ktlint.gradle"