fix(deps): update dependency org.apache.tomcat.embed:tomcat-embed-core to v11.0.21 (#2005)

This PR contains the following updates:

| Package | Change |
[Age](https://docs.renovatebot.com/merge-confidence/) |
[Confidence](https://docs.renovatebot.com/merge-confidence/) |
|---|---|---|---|
|
[org.apache.tomcat.embed:tomcat-embed-core](https://tomcat.apache.org/)
| `11.0.18` → `11.0.21` |
![age](https://developer.mend.io/api/mc/badges/age/maven/org.apache.tomcat.embed:tomcat-embed-core/11.0.21?slim=true)
|
![confidence](https://developer.mend.io/api/mc/badges/confidence/maven/org.apache.tomcat.embed:tomcat-embed-core/11.0.18/11.0.21?slim=true)
|

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examples/example-exemplars-tail-sampling/example-greeting-service/pom.xml

@@ -45,7 +45,7 @@
     <dependency>
       <groupId>org.apache.tomcat.embed</groupId>
       <artifactId>tomcat-embed-core</artifactId>
-      <version>11.0.18</version>
+      <version>11.0.21</version>
     </dependency>
   </dependencies>
 

examples/example-exemplars-tail-sampling/example-hello-world-app/pom.xml

@@ -45,7 +45,7 @@
     <dependency>
       <groupId>org.apache.tomcat.embed</groupId>
       <artifactId>tomcat-embed-core</artifactId>
-      <version>11.0.18</version>
+      <version>11.0.21</version>
     </dependency>
   </dependencies>
 

examples/example-exporter-servlet-tomcat/pom.xml

@@ -44,7 +44,7 @@
     <dependency>
       <groupId>org.apache.tomcat.embed</groupId>
       <artifactId>tomcat-embed-core</artifactId>
-      <version>11.0.18</version>
+      <version>11.0.21</version>
     </dependency>
   </dependencies>
 

integration-tests/it-exporter/it-exporter-servlet-tomcat-sample/pom.xml

@@ -33,7 +33,7 @@
     <dependency>
       <groupId>org.apache.tomcat.embed</groupId>
       <artifactId>tomcat-embed-core</artifactId>
-      <version>11.0.18</version>
+      <version>11.0.21</version>
     </dependency>
   </dependencies>