OIDC OP v4.2.1 now available

[Henri Mikkonen]

The Shibboleth Project has released V4.2.1 of the OIDC OP plugin (see 
release notes at [1])

This is a patch release, addressing a regression bug related to the use 
of frontChannelSuccess-option within logout propagation.

-- Henri Mikkonen, on behalf of the team

[1] 
https://shibboleth.atlassian.net/wiki/spaces/IDPPLUGINS/pages/2776760321/OPReleaseNotes