Ocspresponder Cache possible nullpointer

[ecki]

In this location the result of the weak reference needs to be checked for null (like it is done in the upper half of this method).

https://github.com/bcgit/bc-java/blob/5c35c9a5e79648d7fdf85d7cbaffe8169f249443/prov/src/main/java/org/bouncycastle/jce/provider/OcspCache.java#L199C32-L199C32

problem was discussed on the crypto-dev list by Felix.

[felixdo]

Hey there, thanks for creating the issue. I'm already trying to patch.

[dghgit]

See #1541