Bump springOpenApiVersion from 2.7.0 to 2.8.1 (#257)

Bumps `springOpenApiVersion` from 2.7.0 to 2.8.1.

Updates `org.springdoc:springdoc-openapi-starter-webmvc-api` from 2.7.0 to 2.8.1
- [Release notes](https://github.com/springdoc/springdoc-openapi/releases)
- [Changelog](https://github.com/springdoc/springdoc-openapi/blob/main/CHANGELOG.md)
- [Commits](springdoc/springdoc-openapi@v2.7.0...v2.8.1)

Updates `org.springdoc:springdoc-openapi-starter-webmvc-ui` from 2.7.0 to 2.8.1
- [Release notes](https://github.com/springdoc/springdoc-openapi/releases)
- [Changelog](https://github.com/springdoc/springdoc-openapi/blob/main/CHANGELOG.md)
- [Commits](springdoc/springdoc-openapi@v2.7.0...v2.8.1)

---
updated-dependencies:
- dependency-name: org.springdoc:springdoc-openapi-starter-webmvc-api
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: org.springdoc:springdoc-openapi-starter-webmvc-ui
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

build.gradle

@@ -21,7 +21,7 @@ buildscript {
     ext {
         bouncycastleVersion = "1.79"
         apacheCommonsCollectionsVersion = "4.4"
-        springOpenApiVersion = "2.7.0"
+        springOpenApiVersion = "2.8.1"
         jsoupVersion = "1.18.3"
         jsonPatchVersion = "1.13"
         zxingVersion = "3.5.3"