fix(deps): bump spring-boot BOM to 4.0.7 to resolve spring-webflux 7.0.8 (GHSA-4hfh-6x8g-gwpp) (#391)

Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: Catarina Correia <catarina.correia@getyourguide.com>

Author: 3 people

gradle/libs.versions.toml

@@ -1,6 +1,6 @@
 [versions]
 java = "21"
-spring-boot = "4.0.6"
+spring-boot = "4.0.7"
 spring-dependency-management = "1.1.7"
 openapi-generator = "7.21.0"
 openapi-tools = "0.2.9"