build(deps): Bump logback-core

Bumps logback-core from 1.2.3 to 1.2.9.

---
updated-dependencies:
- dependency-name: ch.qos.logback:logback-core
  dependency-type: direct:production
...

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Author: dependabot[bot]

sentinel-demo/sentinel-demo-log-logback/pom.xml

@@ -25,7 +25,7 @@
         <dependency>
             <groupId>ch.qos.logback</groupId>
             <artifactId>logback-core</artifactId>
-            <version>1.2.3</version>
+            <version>1.2.9</version>
         </dependency>
 
         <dependency>