Bump spring-boot-dependencies from 2.7.7 to 2.7.8

Bumps [spring-boot-dependencies](https://github.com/spring-projects/spring-boot) from 2.7.7 to 2.7.8.
- [Release notes](https://github.com/spring-projects/spring-boot/releases)
- [Commits](spring-projects/spring-boot@v2.7.7...v2.7.8)

---
updated-dependencies:
- dependency-name: org.springframework.boot:spring-boot-dependencies
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

build.gradle

@@ -26,7 +26,7 @@ buildscript {
 		immutablesVersion = "2.9.3"
 		openServiceBrokerVersion = "3.5.3"
 		pmdVersion = "6.29.0"
-		springBootVersion = "2.7.7"
+		springBootVersion = "2.7.8"
 		springCredhubVersion = "2.3.0"
 		springFrameworkVersion = "5.3.22"
 		wiremockVersion = "2.27.2"