Update module-info.java (#426)

pf4j/src/main/java/module-info.java

@@ -26,14 +26,14 @@ module org.pf4j {
     // provides javax.annotation
     requires java.compiler;
 
-    // provided by the ASM library
-    requires org.objectweb.asm;
+    // provided by the ASM library, use "requires static" since it's optional
+    requires static org.objectweb.asm;
 
     // The SLF4J library currently does not provide a module.
     // Version 1.8 provides a module called "org.slf4j". But this version is
     // currently in beta stage. Therefore I'm not sure, if we already like to
     // use it.
-    requires slf4j.api;
+    requires org.slf4j;
 
     // The java-semver library currently does not provide a module.
     // Maybe we should send them a pull request, that at least they provide an

pom.xml

@@ -45,9 +45,9 @@
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <maven.compiler.release>8</maven.compiler.release>
 
-        <slf4j.version>1.7.25</slf4j.version>
+        <slf4j.version>1.7.30</slf4j.version>
         <log4j.version>2.13.1</log4j.version>
-        <asm.version>7.1</asm.version>
+        <asm.version>9.1</asm.version>
 
         <junit.version>5.4.0</junit.version>
         <hamcrest.version>2.1</hamcrest.version>