Do not attempt to pad time string if current length is sufficient (#3676)

* Do not attempt to pad time string if current length is sufficient

* Remove 'final' modifier from local variables

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Co-authored-by: Anna-Karin Salander <[email protected]>

Author: belugabehr

services-custom/dynamodb-enhanced/src/main/java/software/amazon/awssdk/enhanced/dynamodb/internal/converter/ConverterUtils.java

@@ -53,14 +53,19 @@ public static void validateFloat(Float input) {
     }
 
     public static String padLeft(int paddingAmount, int valueToPad) {
+        String result;
         String value = Integer.toString(valueToPad);
-        int padding = paddingAmount - value.length();
-        StringBuilder result = new StringBuilder(paddingAmount);
-        for (int i = 0; i < padding; i++) {
-            result.append('0');
+        if (value.length() == paddingAmount) {
+            result = value;
+        } else {
+            int padding = paddingAmount - value.length();
+            StringBuilder sb = new StringBuilder(paddingAmount);
+            for (int i = 0; i < padding; i++) {
+                sb.append('0');
+            }
+            result = sb.append(value).toString();
         }
-        result.append(value);
-        return result.toString();
+        return result;
     }
 
     public static String[] splitNumberOnDecimal(String valueToSplit) {