Bump spring-boot-starter-security from RELEASE to 2.1.9.RELEASE

Bumps [spring-boot-starter-security](https://github.com/spring-projects/spring-boot) from RELEASE to 2.1.9.RELEASE.
- [Release notes](https://github.com/spring-projects/spring-boot/releases)
- [Commits](https://github.com/spring-projects/spring-boot/commits/v2.1.9.RELEASE)

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

pom.xml

@@ -111,7 +111,7 @@
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-security</artifactId>
-            <version>RELEASE</version>
+            <version>2.1.9.RELEASE</version>
         </dependency>
         <dependency>
             <groupId>org.springframework.boot</groupId>