build(deps): bump org.springframework:spring-context

Bumps [org.springframework:spring-context](https://github.com/spring-projects/spring-framework) from 5.0.6.RELEASE to 5.2.21.RELEASE.
- [Release notes](https://github.com/spring-projects/spring-framework/releases)
- [Commits](spring-projects/spring-framework@v5.0.6.RELEASE...v5.2.21.RELEASE)

---
updated-dependencies:
- dependency-name: org.springframework:spring-context
  dependency-type: direct:production
...

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

pom.xml

@@ -71,7 +71,7 @@
         <maven.compiler.source>1.8</maven.compiler.source>
         <maven.compiler.target>1.8</maven.compiler.target>
         <maven-compiler-plugin.version>3.6.1</maven-compiler-plugin.version>
-        <spring.version>5.0.6.RELEASE</spring.version>
+        <spring.version>5.2.21.RELEASE</spring.version>
         <spring-boot.version>2.0.2.RELEASE</spring-boot.version>
         <spring.webflux.version>2.6.6</spring.webflux.version>
         <springfox-swagger-ui.version>2.7.0</springfox-swagger-ui.version>