fix build logic due to state mutations and break the API accordingly

* remove setName, setFilter, and setTestRunner. Please set these
   options directly when creating the CompileStep.
 * removed unused field
 * remove computeOutFileNames and inline the logic, making clear the
   goal of avoiding state mutations after the build step is created.
3c3cee2cfaAndrew Kelley committed on 4/11/2023, 3:42:14 PMparentd5eab33
5 files changedLine totals unavailable