Fix sonar issues and add DMF tests for maintenance window feature (#655)

* Fix sonar issues.

Signed-off-by: kaizimmerm <kai.zimmermann@bosch-si.com>

* POM cleanup and more sonar issues fixed.

Signed-off-by: kaizimmerm <kai.zimmermann@bosch-si.com>

* Remove unneeded JavaDocs.

Signed-off-by: kaizimmerm <kai.zimmermann@bosch-si.com>

* More sonar issues.

Signed-off-by: kaizimmerm <kai.zimmermann@bosch-si.com>

* More issues.

Signed-off-by: kaizimmerm <kai.zimmermann@bosch-si.com>

* Adapt maintenance window to naming.

Signed-off-by: kaizimmerm <kai.zimmermann@bosch-si.com>

* Add DMF tests.

Signed-off-by: kaizimmerm <kai.zimmermann@bosch-si.com>

* Readibility.

Signed-off-by: kaizimmerm <kai.zimmermann@bosch-si.com>

* Typos fixed.

Signed-off-by: kaizimmerm <kai.zimmermann@bosch-si.com>

pom.xml

@@ -120,7 +120,7 @@
       <!-- Repeatable migrations, Disabling clean etc. -->
       <flyway.version>4.0.3</flyway.version>
       <!-- Improved integration test capabilities -->
-      <spring-amqp.version>1.7.4.RELEASE</spring-amqp.version>
+      <spring-amqp.version>1.7.6.RELEASE</spring-amqp.version>
       <!-- Older versions needed than defined in Boot -->
       <!-- Incompatible changes in 2.2 -->
       <json-path.version>2.0.0</json-path.version>
@@ -149,6 +149,7 @@
       <maven.scm.plugin.version>1.9.4</maven.scm.plugin.version>
 
       <!-- Misc libraries versions - START -->
+      <cron-utils.version>5.0.5</cron-utils.version>
       <jsoup.version>1.8.3</jsoup.version>
       <validation-api.version>2.0.1.Final</validation-api.version>
       <allure.version>1.5.4</allure.version>
@@ -568,6 +569,11 @@
          </dependency>
 
          <!-- Misc -->
+         <dependency>
+            <groupId>com.cronutils</groupId>
+            <artifactId>cron-utils</artifactId>
+            <version>${cron-utils.version}</version>
+         </dependency>
          <dependency>
             <groupId>org.jsoup</groupId>
             <artifactId>jsoup</artifactId>