Fix build dependency

Signed-off-by: Andrew DeMaria <lostonamountain@gmail.com>

libresonic-main/pom.xml

@@ -38,6 +38,10 @@
             <scope>test</scope>
         </dependency>
 
+        <dependency>
+            <groupId>org.springframework</groupId>
+            <artifactId>spring-core</artifactId>
+        </dependency>
 
         <dependency>
             <groupId>org.springframework</groupId>

pom.xml

@@ -95,6 +95,11 @@
 
     <dependencyManagement>
         <dependencies>
+            <dependency>
+                <groupId>org.springframework</groupId>
+                <artifactId>spring-core</artifactId>
+                <version>${spring.version}</version>
+            </dependency>
             <dependency>
                 <groupId>org.springframework</groupId>
                 <artifactId>spring-webmvc</artifactId>