KAFKA-14198: Define separate configuration for Swagger (#12616)

Reviewers: Ismael Juma <ismael@juma.me.uk>

build.gradle

@@ -2535,6 +2535,10 @@ project(':connect:json') {
 }
 
 project(':connect:runtime') {
+  configurations {
+    swagger
+  }
+
   archivesBaseName = "connect-runtime"
 
   dependencies {
@@ -2564,7 +2568,9 @@ project(':connect:runtime') {
     implementation libs.mavenArtifact
     implementation libs.swaggerAnnotations
 
-    compileOnly libs.swaggerJaxrs2
+    // We use this library to generate OpenAPI docs for the REST API, but we don't want or need it at compile
+    // or run time. So, we add it to a separate configuration, which we use later on during docs generation
+    swagger libs.swaggerJaxrs2
 
     testImplementation project(':clients').sourceSets.test.output
     testImplementation project(':core')
@@ -2653,9 +2659,9 @@ project(':connect:runtime') {
   }
 
   task genConnectOpenAPIDocs(type: io.swagger.v3.plugins.gradle.tasks.ResolveTask, dependsOn: setVersionInOpenAPISpec) {
-    classpath = sourceSets.main.compileClasspath + sourceSets.main.runtimeClasspath
+    classpath = sourceSets.main.runtimeClasspath
 
-    buildClasspath = classpath
+    buildClasspath = classpath + configurations.swagger.asCollection()
     outputFileName = 'connect_rest'
     outputFormat = 'YAML'
     prettyPrint = 'TRUE'