Fix capitalization of OpenID in user facing messaging

[jtnord]

Jenkins and plugins versions report

OpenID is OpenID not openid OpenId` or any other casing.

The casing in inconsistent throughout the plugin and should be changed so that it is always OpenID (and possibly OpenID Connect) where connect is used.

What Operating System are you using (both controller, and any agents involved in the problem)?

N/A

Reproduction steps

Search the code /src/main (case insensitively) for openId

Expected Results

All occurrences that would be shown to a user are correctly capitalized as OpenID

Actual Results

There is a mix of casing, often in the same properties file!

Anything else?

No response

Are you interested in contributing a fix?

No response