dub should not build dependencies when target type is a static library

[ghost]

If you have a library set up as "targetType": "staticLibrary" and you have a bunch of other dependencies dub will by default run something like the following:

C:\dev\projects\opengl-tutorials\utility>dub --force -v 2> nul
glfw-drey: ["glfw-drey"]
glad-drey: ["glad-drey"]
glfw-drey: ["glfw-drey"]
glwtf-drey: ["glwtf-drey", "glfw-drey"]
gltut-utility: ["gltut-utility", "glfw-drey", "glad-drey", "glwtf-drey", "glfw-drey"]
Building glfw-drey configuration "glfw-drey", build type debug.
Running dmd...
DMD v2.066 DEBUG
Building glad-drey configuration "glad-drey", build type debug.
Running dmd...
DMD v2.066 DEBUG
Building glwtf-drey configuration "glwtf-drey", build type debug.
Running dmd...
DMD v2.066 DEBUG
Building gltut-utility configuration "library", build type debug.
Running dmd...
DMD v2.066 DEBUG
Target is a library. Skipping execution.

Note that before building the gltut-utility static library it will first build all the dependencies (other static libraries) first. This isn't necessary as building a static library does not require linking, it only requires the proper import paths to its dependencies.