Merge pull request #26253 from dreis2211

* gh-26253:
  Fix GitHub tag determination following main branch rename

Closes gh-26253

buildSrc/src/main/java/org/springframework/boot/build/AsciidoctorConventions.java

@@ -125,7 +125,7 @@ class AsciidoctorConventions {
 
 	private String determineGitHubTag(Project project) {
 		String version = "v" + project.getVersion();
-		return (version.endsWith("-SNAPSHOT")) ? "master" : version;
+		return (version.endsWith("-SNAPSHOT")) ? "main" : version;
 	}
 
 	private void configureOptions(AbstractAsciidoctorTask asciidoctorTask) {