chore(deps): update dependency org.springframework.boot:spring-boot-dependencies to v4

| datasource | package                                           | from   | to    |
| ---------- | ------------------------------------------------- | ------ | ----- |
| maven      | org.springframework.boot:spring-boot-dependencies | 3.5.11 | 4.0.3 |

Author: renovate[bot]

testcontainers-spring-boot-parent/pom.xml

@@ -15,7 +15,7 @@
     <description>Parent pom for all embedded testcontainers</description>
 
     <properties>
-        <spring.boot.version>3.5.11</spring.boot.version>
+        <spring.boot.version>4.0.3</spring.boot.version>
         <spring.cloud.version>2025.0.1</spring.cloud.version>
         <spring.cloud.gcp.version>7.4.5</spring.cloud.gcp.version>
         <equalsverifier.version>4.4.1</equalsverifier.version>