flex: remove redundant change in 'check' (#1466)
flex: remove redundant change in 'check' (#1466)

The test names sed tries to eliminate have changed
over the years (prefix 'test-' dropped, hyphen replaced
by underscore). Moreover, the eliminated tests do pass
since the most recent flex/bison versions.
juergenpf/MSYS2-packages,juergenpf/MSYS2-packages,JPeterMugaas/MSYS2-packages,PiotrVV/MSYS2-packages,Alexpux/MSYS2-packages,mashir43/MSYS2-packages,PiotrVV/MSYS2-packages,PiotrVV/MSYS2-packages,atom2013/MSYS2-packages,PiotrVV/MSYS2-packages,mashir43/MSYS2-packages,juergenpf/MSYS2-packages,waterlan/MSYS2-packages,mashir43/MSYS2-packages,waterlan/MSYS2-packages,JPeterMugaas/MSYS2-packages,juergenpf/MSYS2-packages,waterlan/MSYS2-packages,Alexpux/MSYS2-packages,mati865/MSYS2-packages,Alexpux/MSYS2-packages,mati865/MSYS2-packages,juergenpf/MSYS2-packages,JPeterMugaas/MSYS2-packages,JPeterMugaas/MSYS2-packages,mati865/MSYS2-packages,Alexpux/MSYS2-packages,atom2013/MSYS2-packages,atom2013/MSYS2-packages,mashir43/MSYS2-packages,mati865/MSYS2-packages,atom2013/MSYS2-packages,waterlan/MSYS2-packages