Remove spring boot gradle plugin from boot 2 tests (#14522)

Author: laurit

settings.gradle.kts

@@ -41,8 +41,6 @@ dependencyResolutionManagement {
         plugin("versions", "org.springframework.boot").version(version)
       }
     }
-    // r2dbc is not compatible with earlier versions
-    addSpringBootCatalog("springBoot2", "2.6.15", "2.+")
     // spring boot 3.0 is not compatible with graalvm native image
     addSpringBootCatalog("springBoot31", "3.1.0", "3.+")
     addSpringBootCatalog("springBoot32", "3.2.0", "3.+")

smoke-tests-otel-starter/spring-boot-2/build.gradle.kts

@@ -1,6 +1,5 @@
 plugins {
   id("otel.java-conventions")
-  alias(springBoot2.plugins.versions)
 }
 
 description = "smoke-tests-otel-starter-spring-boot-2"
@@ -13,7 +12,8 @@ dependencies {
   implementation("org.springframework.kafka:spring-kafka")
   implementation("org.springframework.boot:spring-boot-starter-data-mongodb")
   implementation("org.springframework.boot:spring-boot-starter-aop")
-  implementation(platform(org.springframework.boot.gradle.plugin.SpringBootPlugin.BOM_COORDINATES))
+  val testLatestDeps = gradle.startParameter.projectProperties["testLatestDeps"] == "true"
+  implementation(platform("org.springframework.boot:spring-boot-dependencies:" + if (testLatestDeps) "2.+" else "2.6.15"))
 
   implementation(project(":smoke-tests-otel-starter:spring-boot-common"))
 
@@ -23,10 +23,6 @@ dependencies {
   testImplementation("org.springframework.boot:spring-boot-starter-test")
 }
 
-springBoot {
-  mainClass = "io.opentelemetry.spring.smoketest.OtelSpringStarterSmokeTestApplication"
-}
-
 configurations.configureEach {
   resolutionStrategy {
     // our dependency management pins to a version that is not compatible with spring boot 2.7

smoke-tests-otel-starter/spring-boot-reactive-2/build.gradle.kts

@@ -1,13 +1,13 @@
 plugins {
   id("otel.java-conventions")
-  alias(springBoot2.plugins.versions)
 }
 
 description = "smoke-tests-otel-starter-spring-boot-reactive-2"
 
 dependencies {
   implementation(project(":instrumentation:spring:starters:spring-boot-starter"))
-  implementation(platform(org.springframework.boot.gradle.plugin.SpringBootPlugin.BOM_COORDINATES))
+  val testLatestDeps = gradle.startParameter.projectProperties["testLatestDeps"] == "true"
+  implementation(platform("org.springframework.boot:spring-boot-dependencies:" + if (testLatestDeps) "2.+" else "2.6.15"))
 
   implementation(project(":smoke-tests-otel-starter:spring-boot-reactive-common"))
   implementation("org.springframework.boot:spring-boot-starter-webflux")
@@ -20,10 +20,6 @@ dependencies {
   testImplementation("io.projectreactor:reactor-test")
 }
 
-springBoot {
-  mainClass = "io.opentelemetry.spring.smoketest.OtelReactiveSpringStarterSmokeTestApplication"
-}
-
 configurations.configureEach {
   resolutionStrategy {
     // our dependency management pins to a version that is not compatible with spring boot 2.7