Bump quarkus.platform.version

Bumps `quarkus.platform.version` from 3.18.4 to 3.21.3.

Updates `io.quarkus.platform:quarkus-bom` from 3.18.4 to 3.21.3
- [Commits](quarkusio/quarkus-platform@3.18.4...3.21.3)

Updates `io.quarkus.platform:quarkus-amazon-services-bom` from 3.18.4 to 3.21.3
- [Commits](quarkusio/quarkus-platform@3.18.4...3.21.3)

Updates `io.quarkus.platform:quarkus-maven-plugin` from 3.18.4 to 3.21.3
- [Commits](quarkusio/quarkus-platform@3.18.4...3.21.3)

---
updated-dependencies:
- dependency-name: io.quarkus.platform:quarkus-bom
  dependency-version: 3.21.3
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: io.quarkus.platform:quarkus-amazon-services-bom
  dependency-version: 3.21.3
  dependency-type: direct:production
  update-type: version-update:semver-minor
- dependency-name: io.quarkus.platform:quarkus-maven-plugin
  dependency-version: 3.21.3
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

labs/unicorn-store/software/alternatives/unicorn-store-quarkus/pom.xml

@@ -13,7 +13,7 @@
     <maven.compiler.target>11</maven.compiler.target>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
     <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
-    <quarkus.platform.version>3.18.4</quarkus.platform.version>
+    <quarkus.platform.version>3.21.3</quarkus.platform.version>
   </properties>
 
   <dependencyManagement>