build: update builder to Ubuntu 22.04 based builder-jammy-tiny

Note: Images generated with this builder (via `./gradlew bootBuildImage`)
currently fail to run on M2 Macs with the following error message:

`rosetta error: failed to open elf at /lib64/ld-linux-x86-64.so.2`

However, due to the high number of CVEs detected in images created with
`builder-jammy-base`, we switch to `builder-jammy-tiny`.

build.gradle.kts

@@ -79,7 +79,7 @@ tasks {
         val containerImageVersion = System.getenv("CONTAINER_IMAGE_VERSION") ?: "latest"
 
         imageName.set("$containerRegistry/$containerImageName:$containerImageVersion")
-        builder.set("paketobuildpacks/builder-jammy-base")
+        builder.set("paketobuildpacks/builder-jammy-tiny")
         publish.set(false)
 
         docker {