Code cleanup

Signed-off-by: David Joos <david.joos@bosch-si.com>

services/things/persistence/src/test/java/org/eclipse/ditto/services/things/persistence/actors/strategies/commands/ThingsConditionalHeadersValidatorTest.java

@@ -176,9 +176,7 @@ private Command createCommandMock(final Category commandCategory, final String i
                 .ifMatch(EntityTagMatchers.fromCommaSeparatedString(ifMatchHeaderValue))
                 .ifNoneMatch(EntityTagMatchers.fromCommaSeparatedString(ifNoneMatchHeaderValue))
                 .build();
-        final Command commandMock;
-
-        commandMock = mock(Command.class);
+        final Command commandMock = mock(Command.class);
         when(commandMock.getDittoHeaders()).thenReturn(dittoHeaders);
         when(commandMock.getCategory()).thenReturn(commandCategory);