Use update-available for deprecated older images (#3010)

Author: damccorm

plugins/templates-maven-plugin/src/main/java/com/google/cloud/teleport/plugin/maven/TemplatesStageMojo.java

@@ -559,7 +559,7 @@ protected String stageFlexTemplate(
         String trackTag = "public-image-latest";
         String dateSuffix =
             LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyy-MM-dd-HH"));
-        String deprecatedTag = "no-new-use-public-image-newer-available-" + dateSuffix;
+        String deprecatedTag = "update-available-" + dateSuffix;
         if (metadata.isHidden()) {
           trackTag = "no-new-use-public-image-latest";
         } else if (metadata.getName().contains("[Deprecated]")) {