Haskell/Pangram readme file contradicts test file regarding non-ASCII symbols

[arguapacha]

The readme file is not in sync with the test file. It says that the input does not contain non-ASCII symbols, but the test cases include two inputs with non-ASCII symbols

Readme file:

haskell/exercises/practice/pangram/.docs/instructions.md

Line 9 in 890b79b

insensitive. Input will not contain non-ASCII symbols.

Test file:

haskell/exercises/practice/pangram/test/Tests.hs

Line 69 in 890b79b

, Case { description = "with additional non-ascii letters"

[petertseng]

Duplicate of #880