Replace logback-classic dependency with spring-boot-starter-logging

This will reduce the dependencies we have to keep up to date, as
Spring can maintain that.

We can instead focus on keeping Spring up to date and trust that
they are patching logback-classic as and when required.

Author: adrianclay

service/build.gradle

@@ -40,7 +40,7 @@ dependencies {
 	implementation ('org.springframework.boot:spring-boot-starter-webflux')
 
 	// Logging
-	implementation 'ch.qos.logback:logback-classic:1.4.14'
+	implementation 'org.springframework.boot:spring-boot-starter-logging'
 
 	// Infrastructure
 	implementation 'com.amazonaws:aws-java-sdk-s3:1.12.673'