Improve build file

build.gradle

@@ -12,9 +12,9 @@ group = project.maven_group
 
 dependencies {
     // to change the versions see the gradle.properties file
-    minecraft "com.mojang:minecraft:${project.minecraft_version}"
-    mappings "net.fabricmc:yarn:${project.yarn_mappings}:v2"
-    modImplementation "net.fabricmc:fabric-loader:${project.loader_version}"
+    minecraft "com.mojang:minecraft:$minecraft_version"
+    mappings "net.fabricmc:yarn:$yarn_mappings:v2"
+    modImplementation "net.fabricmc:fabric-loader:$loader_version"
 }
 
 processResources {