deps(deps): bump com.icegreen:greenmail from 2.0.1 to 2.1.8

Bumps [com.icegreen:greenmail](https://github.com/greenmail-mail-test/greenmail) from 2.0.1 to 2.1.8.
- [Release notes](https://github.com/greenmail-mail-test/greenmail/releases)
- [Commits](greenmail-mail-test/greenmail@release-2.0.1...release-2.1.8)

---
updated-dependencies:
- dependency-name: com.icegreen:greenmail
  dependency-version: 2.1.8
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

build.gradle

@@ -69,8 +69,8 @@ dependencies {
 
     testImplementation 'org.wiremock:wiremock-standalone:3.13.2'
     testRuntimeOnly 'org.junit.platform:junit-platform-launcher'
-    testImplementation 'com.icegreen:greenmail:2.0.1'
-    testImplementation 'com.icegreen:greenmail-junit5:2.0.1'
+    testImplementation 'com.icegreen:greenmail:2.1.8'
+    testImplementation 'com.icegreen:greenmail-junit5:2.1.8'
 
 }