[Java][native] Fix: useEnumCaseInsensitive option fixed in Java Native Model Enum

[oguzdemirbasci]

useEnumCaseInsensitive option does not work in Java Enum Classes for native library. It is implemented implemented in the default template but not in the native template. This PR copies the conditional equalsIgnoreCase call from default template to native.

Seems like this change was forgotten in this PR: #15273

More details are shared in this issue: #18761

Java Committee Members:
@bbdouglas @sreeshas @jfiala @lukoyanov @cbornet @jeff9finger @karismann @Zomzog @lwlee2608 @martin-mfg

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[wing328]

tested locally to confirm the fix

--- a/src/main/java/org/openapitools/client/model/EnumTest.java
+++ b/src/main/java/org/openapitools/client/model/EnumTest.java
@@ -55,7 +55,7 @@ public enum EnumTest {
   @JsonCreator
   public static EnumTest fromValue(String value) {
     for (EnumTest b : EnumTest.values()) {
-      if (b.value.equals(value)) {
+      if (b.value.equalsIgnoreCase(value)) {
         return b;
       }
     }

thanks for the PR