While de-provisioning the GCP infrastructure, I found the following KMS instance:
projects/tekton-releases/locations/global/keyRings/verified-catalog/cryptoKeys/signing-key/cryptoKeyVersions/1
For posterity, I wanted to track the public key associated with it:
-----BEGIN PUBLIC KEY-----
MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEnnHIQHg/lwx8/iGqH14OdsQEV/pG
JTYrtKZgimUz0BNeTcmrfqd74Yln/J4PvsTzzCaMxCzPPzi4enMOlQKdPA==
-----END PUBLIC KEY-----