remove missing file `packages.config` from project.
remove missing file `packages.config` from project.

YaccConstructor/FStar,A-Manning/FStar,MallabaevAzamat/FStar,MallabaevAzamat/FStar,FStarLang/FStar,hoheinzollern/FStar,MallabaevAzamat/FStar,YaccConstructor/FStar,FStarLang/FStar,hoheinzollern/FStar,A-Manning/FStar,hoheinzollern/FStar,YaccConstructor/FStar,A-Manning/FStar,YaccConstructor/FStar,hoheinzollern/FStar,FStarLang/FStar,MallabaevAzamat/FStar