[Build] Define k8-agent for native gtk.linux.x86_64 only in pipeline

Jenkinsfile

@@ -18,11 +18,14 @@
 def runOnNativeBuildAgent(String platform, Closure body) {
 	def final nativeBuildStageName = 'Build SWT-native binaries'
 	if (platform == 'gtk.linux.x86_64') {
-		return podTemplate(containers: [name: 'swtbuild', image: 'eclipse/platformreleng-centos-swt-build:8',
+		return podTemplate(inheritFrom: 'centos-8', containers: [name: 'swtbuild',
 			resourceRequestCpu:'1000m', resourceRequestMemory:'512Mi',
 			resourceLimitCpu:'2000m', resourceLimitMemory:'4096Mi'
 		]) { node(POD_LABEL) { stage(nativeBuildStageName) { container('swtbuild') {
-			//TODO: install requirements?
+			sh '''
+				sudo apt-get update -qq 
+				sudo apt-get install -qq -y libgtk-3-dev freeglut3-dev webkit2gtk-driver
+			'''
 			body()
 		} } } }
 	} else {