public Builder clearProjectId() {
      projectId_ = getDefaultInstance().getProjectId();
      bitField0_ = (bitField0_ & ~0x00000001);
      onChanged();
      return this;
    }
<pre>
Required. Project id used to create forwarding rule.
</pre>

<code>string project_id = 1 [(.google.api.field_behavior) = REQUIRED];</code>

@return This builder for chaining.
java-vertexai/proto-google-cloud-vertexai-v1/src/main/java/com/google/cloud/vertexai/api/PSCAutomationConfig.java