build(deps): bump org.assertj:assertj-core from 3.27.5 to 3.27.6 (#383)

Bumps [org.assertj:assertj-core](https://github.com/assertj/assertj) from 3.27.5 to 3.27.6.
- [Release notes](https://github.com/assertj/assertj/releases)
- [Commits](assertj/assertj@assertj-build-3.27.5...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]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

gradle/libs.versions.toml

@@ -2,7 +2,7 @@
 format.version = "1.1"
 
 [versions]
-assertj = "3.27.5"
+assertj = "3.27.6"
 checkstyle = "11.0.1"
 edc = "0.15.0-SNAPSHOT"
 # the edc-boot-spi dependency is used only for tests, this fixed version prevents the "chicken-egg" problem