Upgrade jackson to 2.15.4

[varunu28]

This addresses #10 .

Doing an incremental upgrade from the current version i.e. 2.11.4 , the latest version at which build is successful is 2.15.4

https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-core

Upgrading to the next version i.e. 2.16.0 results in test failures with below error log:

Caused by: com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Java 8 optional type `java.util.Optional<com.netflix.conductor.common.metadata.tasks.TaskDef>` not supported by default: add Module "com.fasterxml.jackson.datatype:jackson-datatype-jdk8" to enable handling (through reference chain: com.netflix.conductor.common.metadata.tasks.Task["taskDefinition"])
	at app//com.fasterxml.jackson.databind.exc.InvalidDefinitionException.from(InvalidDefinitionException.java:77)
	at app//com.fasterxml.jackson.databind.SerializerProvider.reportBadDefinition(SerializerProvider.java:1330)
	at app//com.fasterxml.jackson.databind.ser.impl.UnsupportedTypeSerializer.serialize(UnsupportedTypeSerializer.java:35)
	at app//com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:732)
	at app//com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:770)
	at app//com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:183)
	at app//com.fasterxml.jackson.databind.ser.DefaultSerializerProvider._serialize(DefaultSerializerProvider.java:502)
	at app//com.fasterxml.jackson.databind.ser.DefaultSerializerProvider.serializeValue(DefaultSerializerProvider.java:341)
	at app//com.fasterxml.jackson.databind.ObjectMapper._writeValueAndClose(ObjectMapper.java:4793)
	at app//com.fasterxml.jackson.databind.ObjectMapper.writeValueAsString(ObjectMapper.java:4038)
	at app//com.netflix.conductor.cockroachdb.dao.CockroachDBBaseDAO.toJson(CockroachDBBaseDAO.java:158)

[varunu28]

@jun-he Can you please review this change? Thank you 👍

[jun-he]

@varunu28 thanks for the contribution! I will review it ASAP.

[jun-he]

@varunu28 doing the load test right now and will get back to you soon.

[jun-he]

Load test is done and the change looks good. @varunu28 can you rebase the PR and then rerun the write-lock to update the dependencies? Thanks.

[varunu28]

@jun-he I ran the write-lock. Can you please do another review?