similar situation. I tried:

mvn io.quarkus.platform:quarkus-maven-plugin:3.15.1:update -N

And I got this error (and the weblink from where you are supposed to get the certificate is invalid - 404: https://registry.quarkus.io/maven ):

[ERROR] Failed to execute goal io.quarkus.platform:quarkus-maven-plugin:3.0.1.Final:update (default-cli) on project ca-toronto-kogito-ds: Failed to initialize Quarkus extension resolver: Failed to resolve the Quarkus extension registry descriptor of registry.quarkus.io from registry.quarkus.io (https://registry.quarkus.io/maven): Failed to resolve artifact io.quarkus.registry:quarkus-registry-descriptor:json:1.0-SNAPSHOT: The following artifacts could not be resolved: io.quarkus.registry:quarkus-registry-descriptor:json:1.0-SNAPSHOT (absent): Could not transfer artifact io.quarkus.registry:quarkus-registry-descriptor:json:1.0-SNAPSHOT from/to registry.quarkus.io (https://registry.quarkus.io/maven): PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target -> [Help 1]