chore: remove github package

Author: 闫茂源

buildSrc/src/main/groovy/jme3-freetype-font.maven-publish-conventions.gradle

@@ -46,14 +46,6 @@ publishing {
             ossrhUrl = 'https://s01.oss.sonatype.org/service/local/staging/deploy/maven2/'
         }
 
-        maven {
-            name = 'GitHubPackages'
-            url = uri('https://maven.pkg.github.com/jmecn/jme3-freetype-font')
-            credentials {
-                username = System.getenv("GITHUB_ACTOR")
-                password = System.getenv("GITHUB_TOKEN")
-            }
-        }
         maven {
             name = 'OSSRH'
             url = ossrhUrl