When I run the svn command line from the Jenkins shell I get this error:
D:\\Jenkins\\jobs\\Merge Trunk to Stable\\workspace\\stable>svn up --trust-server-ce
This may seem like a horrible answer but after exhausting the other ones, which didn't work for me due to other issues, I choose to go the route of changing the SVN server to not use SSL.
This was only an option because I just setup this server and it's on a totally internal network, but it did eliminate the issue entirely. And I ran out of other options and time.
I also only suggest this incase someone doesn't realize it is even an option. Using SSL would make me feel much better regardless of the server exposure.