chore: bump net.coobird:thumbnailator from 0.4.20 to 0.4.21

Bumps [net.coobird:thumbnailator](https://github.com/coobird/thumbnailator) from 0.4.20 to 0.4.21.
- [Commits](coobird/thumbnailator@0.4.20...0.4.21)

---
updated-dependencies:
- dependency-name: net.coobird:thumbnailator
  dependency-version: 0.4.21
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

build.gradle

@@ -54,7 +54,7 @@ subprojects {
 		implementation 'io.jsonwebtoken:jjwt:0.9.1'
 		implementation 'javax.xml.bind:jaxb-api:2.3.1'
 
-		implementation 'net.coobird:thumbnailator:0.4.20'
+		implementation 'net.coobird:thumbnailator:0.4.21'
 
 		testFixturesImplementation 'org.springframework.boot:spring-boot-starter-test'
 		testFixturesRuntimeOnly 'org.junit.platform:junit-platform-launcher'