[Java] Update templates not to add @Pattern on byte array property (#7153)

* Update Java templates to skip generating @Pattern on byte array properties

* Revert separator changes

* Revert separator changes

samples/server/petstore/spring-mvc-j8-async/src/main/java/org/openapitools/model/FormatTest.java

@@ -227,7 +227,7 @@ public class FormatTest   {
   @ApiModelProperty(required = true, value = "")
   @NotNull
 
-@Pattern(regexp="^(?:[A-Za-z0-9+/]{4})*(?:[A-Za-z0-9+/]{2}==|[A-Za-z0-9+/]{3}=)?$") 
+
   public byte[] getByte() {
     return _byte;
   }