Bump log4j-core from 2.14.1 to 2.15.0 in /tests/examples/JDBC/taosdemo

Bumps log4j-core from 2.14.1 to 2.15.0.

---
updated-dependencies:
- dependency-name: org.apache.logging.log4j:log4j-core
  dependency-type: direct:production
...
Signed-off-by: Ndependabot[bot] <support@github.com>

tests/examples/JDBC/taosdemo/pom.xml

@@ -88,7 +88,7 @@
         <dependency>
             <groupId>org.apache.logging.log4j</groupId>
             <artifactId>log4j-core</artifactId>
-            <version>2.14.1</version>
+            <version>2.15.0</version>
         </dependency>
         <!-- junit -->
         <dependency>