Bump software.amazon.awssdk:bom from 2.27.17 to 2.27.21

Bumps software.amazon.awssdk:bom from 2.27.17 to 2.27.21.

---
updated-dependencies:
- dependency-name: software.amazon.awssdk:bom
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

pom.xml

@@ -59,7 +59,7 @@
     <surefire.version>3.5.0</surefire.version>
 
     <!-- Dependency versions -->
-    <aws.version>2.27.17</aws.version>
+    <aws.version>2.27.21</aws.version>
     <dagger.version>2.52</dagger.version>
     <dropwizard.version>4.0.8</dropwizard.version>
     <failsafe.version>2.4.4</failsafe.version>