Update Spring Boot version and format HTML in ng-web

This commit updates the Spring Boot plugin version from 3.3.3 to 3.3.4 in build.gradle and formats the HTML in ng-web/src/index.html for better readability without changing its functionality.

build.gradle

@@ -1,5 +1,5 @@
 plugins {
-    id "org.springframework.boot" version "3.3.3" apply false
+    id "org.springframework.boot" version "3.3.4" apply false
     id 'io.spring.dependency-management' version '1.1.6' apply false
     id 'org.graalvm.buildtools.native' version '0.10.2' apply false
 }
@@ -88,7 +88,7 @@ configure(subprojects - project(":boot")) { project ->
         implementation("com.google.guava:guava:33.+")
         implementation("com.github.f4b6a3:ulid-creator:5.+")
 
-        implementation 'org.springframework.boot:spring-boot-starter-actuator'
+        implementation("org.springframework.boot:spring-boot-starter-actuator")
         implementation("org.springframework.boot:spring-boot-starter-validation")
 
         implementation("org.springframework.boot:spring-boot-starter-log4j2")