Fix #39 Use slf4j-simple for tests, remove log4j (#53)

Signed-off-by: Andres Almiray <aalmiray@gmail.com>

Author: aalmiray

pom.xml

@@ -114,7 +114,6 @@
             <groupId>com.networknt</groupId>
             <artifactId>json-schema-validator</artifactId>
 			<version>${json.schema.version}</version>
-
         </dependency>
 
 		<dependency>
@@ -123,14 +122,6 @@
 			<version>${slf4j.version}</version>
 		</dependency>
 
-		<dependency>
-			<groupId>org.slf4j</groupId>
-			<artifactId>slf4j-log4j12</artifactId>
-			<version>${slf4j.version}</version>
-			<optional>true</optional>
-			<scope>runtime</scope>
-		</dependency>
-
 		<dependency>
 			<groupId>com.github.package-url</groupId>
 			<artifactId>packageurl-java</artifactId>
@@ -151,6 +142,13 @@
 			<version>${assertj-core.version}</version>
 			<scope>test</scope>
 		</dependency>
+
+		<dependency>
+			<groupId>org.slf4j</groupId>
+			<artifactId>slf4j-simple</artifactId>
+			<version>${slf4j.version}</version>
+			<scope>test</scope>
+		</dependency>
 	</dependencies>
 
 	<build>