tests: Use insecure random for acceptance tests

This reduces startup time for JUnit tests which need random data
to seed the SSHD PRNG. Using /dev/./urandom is necessary as a
workaround on modern Java versions[1].

[1] https://bugs.openjdk.java.net/browse/JDK-6202721
Change-Id: I944f73e93dca131c6947779a3f9f4fb8d87b9a54
1 file changed