Start using dependency management plugin again

This is possible because of spring-io/nohttp#35

This reverts commit f967b11e25.

build.gradle

@@ -1,5 +1,3 @@
-import io.spring.nohttp.gradle.NoHttpCheckstylePlugin
-
 buildscript {
 	dependencies {
 		classpath 'io.spring.gradle:spring-build-conventions:0.0.34.RELEASE'
@@ -11,7 +9,7 @@ buildscript {
 	}
 }
 
-apply plugin: NoHttpCheckstylePlugin
+apply plugin: 'io.spring.convention.root'
 apply plugin: 'io.spring.convention.springdependencymangement'
 apply plugin: 'io.spring.convention.maven'
 apply plugin: 'io.spring.convention.artifactory'
@@ -23,10 +21,6 @@ artifacts {
 	archives file('spring-session-bom.txt')
 }
 
-repositories {
-	mavenCentral()
-}
-
 dependencyManagement {
 	generatedPomCustomization {
 		enabled = true
@@ -82,19 +76,11 @@ task deployArtifacts {
 	description = 'Deploys the artifacts to either Artifactory or Maven Central'
 }
 
-def finalizeDeployArtifacts = project.task("finalizeDeployArtifacts")
-
 if (version.matches(/^.*-RELEASE$/) || version.matches(/^.*-SR\d+$/)) {
-	if (project.hasProperty("ossrhUsername")) {
-		project.ext.nexusUsername = project.ossrhUsername
-		project.ext.nexusPassword = project.ossrhPassword
-		project.getPluginManager().apply("io.codearte.nexus-staging")
-		finalizeDeployArtifacts.dependsOn project.tasks.closeAndReleaseRepository
-		project.nexusStaging.packageGroup = 'org.springframework'
-	}
-
 	deployArtifacts.dependsOn uploadArchives
 }
 else {
 	deployArtifacts.dependsOn artifactoryPublish
 }
+
+sonarqube.skipProject = true