public Containerizer setToolVersion(@Nullable String toolVersion) {
    this.toolVersion = toolVersion;
    return this;
  }
Sets the version of the tool that is using Jib Core. The tool version is sent as part of the
{@code User-Agent} in registry requests and set as the {@code created_by} in the container
layer history. Defaults to the current version of jib-core.

@param toolVersion the name of the tool using this library
@return this
jib-core/src/main/java/com/google/cloud/tools/jib/api/Containerizer.java