Bump jackson-databind in /aws-lambda-java-serialization (#323)

Bumps [jackson-databind](https://github.com/FasterXML/jackson) from 2.10.0 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
...

Signed-off-by: dependabot[bot] <[email protected]>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Carl Zogheib <[email protected]>
Co-authored-by: Alexander Smirnov <[email protected]>

Author: 3 people

aws-lambda-java-serialization/pom.xml

@@ -39,7 +39,7 @@
         <dependency>
             <groupId>com.fasterxml.jackson.core</groupId>
             <artifactId>jackson-databind</artifactId>
-            <version>2.10.0</version>
+            <version>2.12.6.1</version>
         </dependency>
         <dependency>
             <groupId>com.google.code.gson</groupId>