bump spring-boot-starter-jetty from 3.0.0-RC1 to 3.0.0-RC2

jetty 11 only runs against servlet api 5, but spring boot 3 will be launched with servlet api 6.
solution for now seems to be an explicit downgrade of our servlet api dependency and wait for jetty 12 to release.

background: spring-projects/spring-framework#29435

build.gradle

@@ -70,7 +70,10 @@ dependencies {
     implementation 'org.modelmapper:modelmapper:3.1.0'
     implementation 'org.jooq:jool:0.9.14'
 
-    implementation('org.springframework.boot:spring-boot-starter-jetty:3.0.0-RC1') {
+    // https://github.com/spring-projects/spring-framework/issues/29435
+    implementation('jakarta.servlet:jakarta.servlet-api:5.0.0')
+    implementation('org.springframework.boot:spring-boot-starter-jetty:3.0.0-RC2') {
+        exclude group: 'jakarta.servlet', module: 'jakarta.servlet-api' // until jetty 12
         exclude module: 'jetty-xml'
     }
     implementation('org.springframework.boot:spring-boot-starter-web:3.0.0-RC2') {
@@ -87,6 +90,7 @@ dependencies {
         exclude group: 'bouncycastle'
     }
 
+    testImplementation('jakarta.servlet:jakarta.servlet-api:6.0.0')
     testImplementation 'org.springframework.boot:spring-boot-starter-test:3.0.0-M5'
     testImplementation 'org.junit.jupiter:junit-jupiter-params:5.9.1'
     testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.9.1'