Bump org.assertj:assertj-core from 3.27.4 to 3.27.6 in /modules/r2dbc

Bumps [org.assertj:assertj-core](https://github.com/assertj/assertj) from 3.27.4 to 3.27.6.
- [Release notes](https://github.com/assertj/assertj/releases)
- [Commits](assertj/assertj@assertj-build-3.27.4...assertj-build-3.27.6)

---
updated-dependencies:
- dependency-name: org.assertj:assertj-core
  dependency-version: 3.27.6
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

modules/r2dbc/build.gradle

@@ -11,12 +11,12 @@ dependencies {
     testRuntimeOnly 'org.junit.platform:junit-platform-launcher:1.11.0'
 
     testImplementation 'org.junit.jupiter:junit-jupiter:5.13.4'
-    testImplementation 'org.assertj:assertj-core:3.27.4'
+    testImplementation 'org.assertj:assertj-core:3.27.6'
     testImplementation 'io.r2dbc:r2dbc-postgresql:0.8.13.RELEASE'
     testImplementation project(':testcontainers-postgresql')
 
     testFixturesImplementation 'io.projectreactor:reactor-core:3.7.9'
-    testFixturesImplementation 'org.assertj:assertj-core:3.27.4'
+    testFixturesImplementation 'org.assertj:assertj-core:3.27.6'
     testFixturesImplementation 'org.junit.jupiter:junit-jupiter:5.13.4'
 }