Update public build file to use GitHubPackages for publishing

GitOrigin-RevId: 80c834adc4ec14dcb0ba9858f480eed300cdae9b

Author: RyanHecht

build.gradle

@@ -80,13 +80,18 @@ shadowJar.archiveFileName = "ShowScript-all.jar"
 
 publishing {
     publications {
-        maven(MavenPublication) {
-            from(components.java)
+        gpr(MavenPublication) {
+            from components.java
         }
     }
     repositories {
         maven {
-            url = uri('https://repo.maven.apache.org/maven2/')
+            name = "GitHubPackages"
+            url = uri("https://maven.pkg.github.com/OWNER/REPOSITORY")
+            credentials {
+                username = project.findProperty("gpr.user") ?: System.getenv("USERNAME")
+                password = project.findProperty("gpr.key") ?: System.getenv("TOKEN")
+            }
         }
     }
 }