Update Jackson and JUnit

[yhtMinceraft1010X]

These are the current versions of the JUnit and Jackson dependencies in build.gradle:

addressbook-level3/build.gradle

Line 44 in 865de62

String jUnitVersion = '5.4.0'

addressbook-level3/build.gradle

Lines 60 to 61 in 865de62

	implementation group: 'com.fasterxml.jackson.core', name: 'jackson-databind', version: '2.7.0'
	implementation group: 'com.fasterxml.jackson.datatype', name: 'jackson-datatype-jsr310', version: '2.7.4'

The latest versions are:

• JUnit: 5.8.2
• Jackson Databind: 2.13.2.2
• Jackson Datatype JSR310: 2.13.2

As a side note, some branches of Duke (e.g. add-gradle-support) also have an outdated JUnit version.

[Eclipse-Dominator]

In regards to upgrading Jackson, I have noticed some behavior change details found here.

In particular Serializing object to file is changed from saving as relative path to absolute path which could lead to undesirable effects. detail here