gpg key expired

$ echo "deb [arch=amd64] http://storage.googleapis.com/tensorflow-serving-apt stable tensorflow-model-server tensorflow-model-server-universal" | sudo tee /etc/apt/sources.list.d/tensorflow-serving.list && \
curl https://storage.googleapis.com/tensorflow-serving-apt/tensorflow-serving.release.pub.gpg | sudo apt-key add -

$ apt-get update
W: GPG error: http://storage.googleapis.com/tensorflow-serving-apt stable InRelease: The following signatures were invalid: EXPKEYSIG 544B7F63BF9E4D5F Tensorflow Serving Developer (Tensorflow Serving APT repository key) <tensorflow-serving-dev@googlegroups.com>
E: The repository 'http://storage.googleapis.com/tensorflow-serving-apt stable InRelease' is not signed

$ apt-key list
...
pub   rsa4096 2017-07-13 [SC] [expired: 2022-07-19]
uid           [ expired] Tensorflow Serving Developer (Tensorflow Serving APT repository key) <tensorflow-serving-dev@googlegroups.com>
...