build: Add missing expanded property

Author: BlayTheNinth

buildSrc/src/main/groovy/multiloader-common.gradle

@@ -88,6 +88,7 @@ processResources {
             "version": version,
             "group": project.group, //Else we target the task's group.
             "minecraft_version": minecraft_version,
+            "minimum_minecraft_version": minimum_minecraft_version,
             "forge_version": forge_version,
             "forge_loader_version_range": forge_loader_version_range,
             "forge_version_range": forge_version_range,