@java.lang.Override
    public int getSerializedSize() {
      int size = memoizedSize;
      if (size != -1) return size;

      size = 0;
      if (!com.google.protobuf.GeneratedMessageV3.isStringEmpty(apiKeySecretVersion_)) {
        size += com.google.protobuf.GeneratedMessageV3.computeStringSize(1, apiKeySecretVersion_);
      }
      size += getUnknownFields().getSerializedSize();
      memoizedSize = size;
      return size;
    }
<pre>
Required. The SecretManager secret version resource name storing API key.
e.g. projects/{project}/secrets/{secret}/versions/{version}
</pre>

<code>
string api_key_secret_version = 1 [(.google.api.field_behavior) = REQUIRED, (.google.api.resource_reference) = { ... }
</code>

@return The bytes for apiKeySecretVersion.
java-vertexai/proto-google-cloud-vertexai-v1/src/main/java/com/google/cloud/vertexai/api/ApiAuth.java