nzbhydra2: use openjdk11

[jojosch]

Motivation for this change

Use openjdk11 for nzbhydra2 ("You need Java (at least 8, at most 15)." https://github.com/theotherp/nzbhydra2/#how-to-run / theotherp/nzbhydra2#697).

With the default jre (version 16) nzbhydra2 does not start (nixos/tests/nzbhydra2.nix also fails).

Things done

• Tested using sandboxing (nix.useSandbox on NixOS, or option sandbox in nix.conf on non-NixOS linux)
• Built on platform(s)
  • NixOS
  • macOS
  • other Linux distributions
• Tested via one or more NixOS test(s) if existing and applicable for the change (look inside nixos/tests)
• Tested compilation of all pkgs that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Determined the impact on package closure size (by running nix path-info -S before and after)

/nix/store/wp7ywmvmrfznqqwfyrh61rjh6qp9qjmz-nzbhydra2-3.13.2	 1528118504 (before)
/nix/store/bc9605igp1x9a50g7iw3k0ikf0bxs1kn-nzbhydra2-3.13.2	 1339522568

• Ensured that relevant documentation is up to date
• Fits CONTRIBUTING.md.

[SuperSandro2000]

diff LGTM

[danielfullmer]

Also needed for ZHF #122042