Use content instead of filter

Co-authored-by: Raven Szewczyk <git@eigenraven.me>

build.gradle

@@ -601,7 +601,7 @@ repositories {
         maven {
             name = "ic2"
             url = getURL("https://maven.ic2.player.to/", "https://maven2.ic2.player.to/")
-            filter {
+            content {
                 includeGroup "net.industrial-craft"
             }
             metadataSources {