Test failure: TextLens.range gets "" if invalid range

Built with GHC 8.4:
```
Failures:

  test/Spec.hs:136:
  1) TextLens.range gets "" if invalid range
       uncaught exception: ErrorCall (Data.Text.Array.new: size overflow
       CallStack (from HasCallStack):
         error, called at libraries/text/Data/Text/Array.hs:132:20 in text-1.2.3.0:Data.Text.Array)

Randomized with seed 856691866

Finished in 0.0017 seconds
```