[Java] regenerate samples to fix pipeline error

Author: fanqiewanzi

samples/client/petstore/java/okhttp-gson/.openapi-generator/FILES

@@ -257,5 +257,3 @@ src/main/java/org/openapitools/client/model/Value.java
 src/main/java/org/openapitools/client/model/Variable.java
 src/main/java/org/openapitools/client/model/Whale.java
 src/main/java/org/openapitools/client/model/Zebra.java
-src/test/java/org/openapitools/client/model/NullableEnumTest.java
-src/test/java/org/openapitools/client/model/RequiredNullableBodyTest.java

samples/client/petstore/java/okhttp-gson/src/main/java/org/openapitools/client/model/RequiredNullableBody.java

@@ -57,7 +57,7 @@
 /**
  * RequiredNullableBody
  */
-@javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen", comments = "Generator version: 7.6.0-SNAPSHOT")
+@javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen", comments = "Generator version: 7.7.0-SNAPSHOT")
 public class RequiredNullableBody {
   public static final String SERIALIZED_NAME_INTEGER_PROP = "integer_prop";
   @SerializedName(SERIALIZED_NAME_INTEGER_PROP)