* fix(progress): add failing test
The progress bar component does not render the gradient 100% correctly:
The very last color that appears in the rendered progress bar should be
the second color defined in the gradient but it is not, due to an
off-by-one one error.
This test case shows this. The next commit will contain the fix.
* fix(progress): use the second gradient color as the last char of the bar
Due to an off-by-one error, the very last rendered color+char was never
exactly the second specified gradient color. The fixed code looks less
elegant unfortunately, but now the last color is the desired one.
