[MNG-6829] Replace StringUtils#isEmpty(String) & #isNotEmpty(String)

Last batch of is(Not)Empty for https://issues.apache.org/jira/browse/MNG-6829
These are the smallest change sets, hence why I opened more at the same time.
After this we can target the next most often used method from the StringUtils classes.


Use this link to re-run the recipe: https://public.moderne.io/recipes/org.openrewrite.java.migrate.apache.commons.lang.IsNotEmptyToJdk?organizationId=QXBhY2hlIE1hdmVu

Co-authored-by: Moderne <team@moderne.io>

src/main/java/org/apache/maven/archiver/MavenArchiver.java

@@ -223,7 +223,7 @@ private void addManifestAttribute(Manifest manifest, Map<String, String> map, St
     }
 
     private void addManifestAttribute(Manifest manifest, String key, String value) throws ManifestException {
-        if (!StringUtils.isEmpty(value)) {
+        if (!(value == null || value.isEmpty())) {
             Manifest.Attribute attr = new Manifest.Attribute(key, value);
             manifest.addConfiguredAttribute(attr);
         } else {
@@ -772,7 +772,7 @@ public static Optional<Instant> parseBuildOutputTimestamp(String outputTimestamp
         }
 
         // Number representing seconds since the epoch
-        if (StringUtils.isNotEmpty(outputTimestamp) && StringUtils.isNumeric(outputTimestamp)) {
+        if ((outputTimestamp != null && !outputTimestamp.isEmpty()) && StringUtils.isNumeric(outputTimestamp)) {
             return Optional.of(Instant.ofEpochSecond(Long.parseLong(outputTimestamp)));
         }