public Builder fileManifest(FileManifest fileManifest) {
            this.fileManifest = fileManifest;
            return this;
        }
Sets the <strong>required</strong> {@link FileManifest} to use
in the plugin.

@param fileManifest FileManifest to use.
@return Returns the builder.
smithy-build/src/main/java/software/amazon/smithy/build/PluginContext.java