fix Issue 11365 - Allow D source file names to have no extension (or an arbitrary extension)
fix Issue 11518 - DMD segfault on multiple template match

Incomplete `specType`, like as (T : A!T), should not be used during determination of template partial specialization order.
Merge pull request #2769 from 9rnsr/fix11518

Issue 11518 - DMD segfault on multiple template match
Merge pull request #2731 from WalterBright/fix11365

fix Issue 11365 - Allow D source file names to have no extension (or an arbitrary extension)