{Address,Customer,TypeAliasTest}: use explicit scoping

src/test/java/net/kemitix/mon/Address.java

@@ -33,7 +33,7 @@ class Address {
 
     private final String street;
 
-    String getStreet() {
+    protected String getStreet() {
         return street;
     }
 }

src/test/java/net/kemitix/mon/Customer.java

@@ -33,7 +33,7 @@ class Customer {
 
     private final Address address;
 
-    Address getAddress() {
+    protected Address getAddress() {
         return address;
     }
 

src/test/java/net/kemitix/mon/TypeAliasTest.java

@@ -74,7 +74,7 @@ public class TypeAliasTest {
             super(value);
         }
 
-        static AnAlias of(final String value) {
+        protected static AnAlias of(final String value) {
             return new AnAlias(value);
         }
     }