I'm using `dub build -b docs` as a way to detect when I did ddoc
wrong, such as mismatching `Params` sections and actual parameter
names.
Sadly one of the dependencies I (indirectly) use already *has*
incorrect ddoc, and it prevents me from building my own docs as
it halts the process.
```
$ dub build -b docs
Starting Performing "docs" build using /usr/bin/dmd for
x86_64.
Building arsd-official:characterencodings 10.9.10 [library]
Building arsd-official:dom 10.9.10 [library]
Building mir-core 1.7.1 [library]
Building mir-algorithm 3.22.3 [default]
../../../home/zorael/.dub/packages/mir-algorithm/3.22.3/mir-algorithm/source/mir/interpolate/constant.d(275,6):
Warning: Ddoc: function declaration has no parameter 'grid'
../../../home/zorael/.dub/packages/mir-algorithm/3.22.3/mir-algorithm/source/mir/polynomial.d(93,1):
Warning: Ddoc: function declaration has no parameter 'F'
../../../home/zorael/.dub/packages/mir-algorithm/3.22.3/mir-algorithm/source/mir/string_map.d(35,1):
Warning: Ddoc: function declaration has no parameter 'U'
Error: warnings are treated as errors
Use -wi if you wish to treat warnings only as
informational.
Error /usr/bin/dmd failed with exit code 1.
```
What can I do here? dub doesn't seem to have a `-wi` equivalent
and I don't see a way to pass it on to dmd. The immediate idea to
do `DFLAGS=-wi dub build -b docs` just gives the same results.
