Bump jsonUnitVersion from 2.11.1 to 2.18.1 (#66)

Bumps `jsonUnitVersion` from 2.11.1 to 2.18.1.

Updates `json-unit` from 2.11.1 to 2.18.1
- [Release notes](https://github.com/lukas-krecan/JsonUnit/releases)
- [Commits](lukas-krecan/JsonUnit@json-unit-parent-2.11.1...json-unit-parent-2.18.1)

Updates `json-unit-assertj` from 2.11.1 to 2.18.1
- [Release notes](https://github.com/lukas-krecan/JsonUnit/releases)
- [Commits](lukas-krecan/JsonUnit@json-unit-parent-2.11.1...json-unit-parent-2.18.1)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Co-authored-by: dependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

Author: dependabot-preview[bot]

pom.xml

@@ -36,7 +36,7 @@
     <jettyVersion>9.4.30.v20200611</jettyVersion>
     <jgitVersion>5.8.0.202006091008-r</jgitVersion>
     <jsonVersion>20160810</jsonVersion>
-    <jsonUnitVersion>2.11.1</jsonUnitVersion>
+    <jsonUnitVersion>2.18.1</jsonUnitVersion>
     <junitVersion>4.13</junitVersion>
     <junit5Version>5.6.2</junit5Version>
     <log4jVersion>2.7</log4jVersion>