fix: test fix

protoc-gen-openapiv2/internal/genopenapi/template.go

@@ -849,13 +849,29 @@ func schemaOfField(f *descriptor.Field, reg *descriptor.Registry, refs refMap) o
 		}
 	}
 
+	ret.Required = arrayUniq(ret.Required)
+
 	if reg.GetProto3OptionalNullable() && f.GetProto3Optional() {
 		ret.XNullable = true
 	}
 
 	return ret
 }
 
+func arrayUniq[T comparable](array []T) []T {
+	seen := make(map[T]struct{})
+	j := 0
+	for _, v := range array {
+		if _, ok := seen[v]; ok {
+			continue
+		}
+		seen[v] = struct{}{}
+		array[j] = v
+		j++
+	}
+	return array[:j]
+}
+
 // primitiveSchema returns a pair of "Type" and "Format" in JSON Schema for
 // the given primitive field type.
 // The last return parameter is true iff the field type is actually primitive.