Do not exclude `package.d` with newer compilers

[andre2007]

As the related issue 11847 is fixed, could we include package.d again for newer compiler versions?

dub test -b syntax Generating test runner configuration 'arsd-official-test-library' for 'library' (library). Excluding package.d file from test due to https://issues.dlang.org/show_bug.cgi?id=11847 Performing "syntax" build using C:\Develop\D\dmd2\windows\bin\dmd.exe for x86_64.

[Geod24]

Modified the title to be a bit more descriptive of the action to take. Note that the fix for this is in stable, but didn't make it to 2.090.1 AFAICS (https://github.com/dlang/dmd/commit/fffe6be43e295ea489afc1de0291bf99af0956e8)

[WebFreak001]

it made it in with 2.091.0

Also this issue was before only applying to single level packages, so we can add exceptions for those for any version.

Even simpler: you can use import p0 = some.mod as workaround for the bug, so we don't have to write compiler version-specific code at all

[WebFreak001]

See #424