Fix varargs warning in WolfSSLJDK8Helper.java

[cconlon]

This PR fixes one warning that may show up in WolfSSLJDK8Helper.java:

compile-nativeheaderdir:
    [javac] Compiling 54 source files to /var/lib/jenkins/workspace/nightly-wolfssljni-jsse-extra/wolfjsse_tests/wolfssljni/build
    [javac] /var/lib/jenkins/workspace/nightly-wolfssljni-jsse-extra/wolfjsse_tests/wolfssljni/src/java/com/wolfssl/provider/jsse/adapter/WolfSSLJDK8Helper.java:135: warning: non-varargs call of varargs method with inexact argument type for last parameter;
    [javac]                         m.invoke(out, appProtos);
    [javac]                                       ^
    [javac]   cast to Object for a varargs call
    [javac]   cast to Object[] for a non-varargs call and to suppress this warning
    [javac] 1 warning