Allow loading extension-lib 1.3

(Which doesn't actually exist yet, but will at some point after the next major release)

app/src/main/java/eu/kanade/tachiyomi/extension/util/ExtensionLoader.kt

@@ -35,7 +35,7 @@ internal object ExtensionLoader {
     private const val METADATA_SOURCE_FACTORY = "tachiyomi.extension.factory"
     private const val METADATA_NSFW = "tachiyomi.extension.nsfw"
     const val LIB_VERSION_MIN = 1.2
-    const val LIB_VERSION_MAX = 1.2
+    const val LIB_VERSION_MAX = 1.3
 
     private const val PACKAGE_FLAGS = PackageManager.GET_CONFIGURATIONS or PackageManager.GET_SIGNATURES