Bump jackson-databind from 2.10.1 to 2.12.6.1 in /tests/milvustest (#347)

Bumps [jackson-databind](https://github.com/FasterXML/jackson) from 2.10.1 to 2.12.6.1.
- [Release notes](https://github.com/FasterXML/jackson/releases)
- [Commits](https://github.com/FasterXML/jackson/commits)

---
updated-dependencies:
- dependency-name: com.fasterxml.jackson.core:jackson-databind
  dependency-type: direct:production
...

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tests/milvustest/pom.xml

@@ -68,7 +68,7 @@
         <dependency>
             <groupId>com.fasterxml.jackson.core</groupId>
             <artifactId>jackson-databind</artifactId>
-            <version>2.10.1</version>
+            <version>2.12.6.1</version>
         </dependency>
         <dependency>
             <groupId>com.fasterxml.jackson.core</groupId>