"default" values in Nixpkgs manual can *somehow* be escaped by the
documentation back to their original string form.
The following ends up escaped into the manual as `"${pkgs.hello}"`.
```
default = "${pkgs.hello}";
```
The methods for this magic have not been found.
Instead, we just change the default strict `handleEvalIssue` so that it
does absolutely nothing and lets them through.
Anyway we won't be building them.
Actual work should be done to figure out why those `default = pkgs.___`
cause issues *only* with our docs generation, and don't fail the NixOS
channels :/