CROW_AMALGAMATE fails with CMake Ninja generator

When trying to build with `CROW_AMALGAMATE=ON` and `-G Ninja`the

```

ninja: error: '<...>/Crow/include/*.h', needed by 'crow_all.h', missing and no known rule to make it

```

error is produced for me on CMake 3.30.2



Seems like globbing is not explicitly supported in `DEPENDS` argument of `add_custom_command` and it just happens to work with the Makefile generator.



As a solution, it is possible to use globbing via https://cmake.org/cmake/help/latest/command/file.html#glob. It is not the recommended way, but would probably work no worse than the current approach - the recommended way is to spell all of the dependencies explicitly.



I can make a pull request with either fix if you are interested. 



Full configure command for reference:

```

/usr/bin/cmake -DCROW_AMALGAMATE=ON -S. -Bbuild -G Ninja

```

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