Prefix output to avoid random ok to confuse test parser

Prefix output to avoid random ok to confuse test parser

Prefix output of generated dh parameters to avoid misinterpretation
of lines beginning with ok[^a-zA-Z0-9] as a testresult.

Also corrected indent and removed useless comma after last item.

Fixes #17480

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/17689)