Fix code scanning alert - jackson-databind

[corneil]

Tracking issue for:

• https://github.com/spring-cloud/spring-cloud-deployer/security/code-scanning/24
• https://github.com/spring-cloud/spring-cloud-deployer/security/code-scanning/23
• https://github.com/spring-cloud/spring-cloud-deployer/security/code-scanning/22
• https://github.com/spring-cloud/spring-cloud-deployer/security/code-scanning/8
• https://github.com/spring-cloud/spring-cloud-deployer/security/code-scanning/7
• https://github.com/spring-cloud/spring-cloud-deployer/security/code-scanning/6