Try the 'exit /b' trick to stop makelibs.bat from terminating build.bat

when run from Gitlab-Runner (CI) using shell="cmd"

src/sbbs3/ctrl/makelibs.bat

@@ -13,4 +13,5 @@ coff2omf %dllsrc%\sbbs.lib sbbs.lib
 implib -a mailsrvr.lib 	%dllsrc%\mailsrvr.dll
 implib -a ftpsrvr.lib 	%dllsrc%\ftpsrvr.dll
 implib -a websrvr.lib 	%dllsrc%\websrvr.dll
-implib -a services.lib	%dllsrc%\services.dll
\ No newline at end of file
+implib -a services.lib	%dllsrc%\services.dll
+exit /b