Use code includes and tabs in connections.adoc

See gh-22171

framework-docs/framework-docs.gradle

@@ -60,12 +60,15 @@ repositories {
 
 dependencies {
 	api(project(":spring-context"))
+	api(project(":spring-jdbc"))
 	api(project(":spring-jms"))
 	api(project(":spring-web"))
 
 	api("org.jetbrains.kotlin:kotlin-stdlib")
 	api("jakarta.jms:jakarta.jms-api")
 	api("jakarta.servlet:jakarta.servlet-api")
+	api("org.apache.commons:commons-dbcp2:2.11.0")
+	api("com.mchange:c3p0:0.9.5.5")
 
 	implementation(project(":spring-core-test"))
 	implementation("org.assertj:assertj-core")